WO2022088200A1

WO2022088200A1 - Video transmission method and apparatus, and mobile platform and computer-readable storage medium

Info

Publication number: WO2022088200A1
Application number: PCT/CN2020/125999
Authority: WO
Inventors: 王星; 冯颖臻
Original assignee: 深圳市大疆创新科技有限公司
Priority date: 2020-11-02
Filing date: 2020-11-02
Publication date: 2022-05-05

Abstract

A video transmission method and apparatus, and a mobile platform and a computer-readable storage medium. The method comprises: adjusting a first coding compression ratio of a first type of video frames (S101); performing, according to the adjusted first coding compression ratio, coding on a first video frame to be coded, so as to obtain a first video frame (S102); performing, on the basis of the first video frame, coding on a second video frame to be coded, so as to obtain a second video frame (S103); and transmitting the second video frame to a terminal device, such that the terminal device performs decoding on the second video frame on the basis of the first video frame (S104). The present application can ensure the reliability of wireless image transmission.

Description

Video transmission method, device, removable platform, and computer-readable storage medium

technical field

The present application relates to the technical field of wireless image transmission, and in particular, to a video transmission method, device, movable platform, and computer-readable storage medium.

Background technique

At present, the movable platform can transmit the captured video to the terminal device through wireless communication, and the terminal device displays the received video. In the process of video transmission, the channel quality of the wireless channel between the mobile platform and the terminal device will change with the distance between the mobile platform and the terminal device, especially between the mobile platform and the terminal device. When the distance is long, the channel quality of the wireless channel is poor, which will lead to the degradation of the transmitted video quality or the transmission freeze. The reliability and video quality of the wireless image transmission cannot be guaranteed, and the user experience is not good.

SUMMARY OF THE INVENTION

Based on this, the embodiments of the present application provide a video transmission method, device, movable platform, and computer-readable storage medium, which aim to solve the problem of degradation of transmitted video quality or transmission freeze, and ensure the reliability of wireless image transmission. and video quality.

In the first aspect, an embodiment of the present application provides a video transmission method, which is applied to a movable platform, where the movable platform includes a photographing device, and the initial video frame captured by the photographing device can pass through the movable platform after being encoded. The wireless channel between the terminal device and the terminal device is transmitted to the terminal device, and the method includes:

adjusting the first coding compression ratio of the first type of video frame according to the channel bandwidth of the wireless channel;

Encode the first to-be-encoded video frame in the initial video frame according to the adjusted first encoding and compression ratio to obtain a first video frame, and transmit the first video frame to the terminal device;

Taking the first video frame as a reference video frame, encoding the second to-be-encoded video frame in the initial video frame to obtain a second video frame;

The second video frame is transmitted to the terminal device, so that the terminal device uses the first video frame as a reference video frame to decode the second video frame.

In a second aspect, an embodiment of the present application further provides a video transmission device, which is applied to a movable platform, where the movable platform includes a shooting device, and an initial video frame captured by the shooting device can pass through the movable platform after being encoded. The wireless channel between the platform and the terminal device is transmitted to the terminal device;

The video transmission device includes a memory and a processor;

the memory is used to store computer programs;

The processor is configured to execute the computer program and implement the following steps when executing the computer program:

In a third aspect, the embodiments of the present application also provide a movable platform, including:

Platform ontology;

a power system, arranged on the platform body, for providing moving power for the movable platform;

a photographing device, arranged on the platform body, for photographing an initial video frame;

The above video transmission device is provided in the platform body, and is used for encoding the initial video frame captured by the photographing device and for transmitting the encoded initial video frame to the terminal device.

In a fourth aspect, an embodiment of the present application further provides a computer-readable storage medium, where the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the processor implements the above-mentioned The steps of the video transmission method.

Embodiments of the present application provide a video transmission method, device, movable platform, and computer-readable storage medium, which adjust the first encoding of the first type of video frame through the channel bandwidth of the wireless channel between the movable platform and the terminal device. compression ratio, and then encode the first video frame to be encoded in the initial video frame captured by the photographing device according to the adjusted first encoding compression ratio to obtain the first video frame, and transmit the first video frame to the terminal device, and take the first video frame as a reference video frame, encode the second to-be-encoded video frame in the initial video frame to obtain a second video frame, and finally transmit the second video frame to the terminal device for the terminal device Taking the first video frame as a reference video frame, the second video frame is decoded, so that the mobile platform can adaptively adjust the coding and compression ratio based on the channel bandwidth, so as to reduce or increase the data amount of the transmitted video frame to solve the problem of transmission problems. If the video quality is degraded or the transmission is stuck, the reliability and video quality of wireless video transmission are guaranteed.

It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not limiting of the present application.

Description of drawings

In order to explain the technical solutions of the embodiments of the present application more clearly, the following briefly introduces the accompanying drawings used in the description of the embodiments. For those of ordinary skill, other drawings can also be obtained from these drawings without any creative effort.

FIG. 1 is a schematic diagram of a scene for implementing the video transmission method provided by the embodiment of the present application;

2 is a schematic flowchart of steps of a video transmission method provided by an embodiment of the present application;

Fig. 3 is the sub-step schematic flow chart of the video transmission method in Fig. 2;

4 is a schematic flowchart of steps of another video transmission method provided by an embodiment of the present application;

Fig. 5 is the sub-step schematic flow chart of the video transmission method in Fig. 4;

6 is a schematic block diagram of the structure of a video transmission apparatus provided by an embodiment of the present application;

FIG. 7 is a schematic structural block diagram of a movable platform provided by an embodiment of the present application.

Detailed ways

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

The flowcharts shown in the figures are for illustration only, and do not necessarily include all contents and operations/steps, nor do they have to be performed in the order described. For example, some operations/steps can also be decomposed, combined or partially combined, so the actual execution order may be changed according to the actual situation.

Some embodiments of the present application will be described in detail below with reference to the accompanying drawings. The embodiments described below and features in the embodiments may be combined with each other without conflict.

In order to solve the above problems, the embodiments of the present application provide a video transmission method, device, movable platform, and computer-readable storage medium, which adjust the first type of video through the channel bandwidth of the wireless channel between the movable platform and the terminal device. The first encoding and compression ratio of the frame, and then encoding the first to-be-encoded video frame in the initial video frame captured by the photographing device according to the adjusted first encoding and compression ratio to obtain the first video frame, and the first video frame transmitting to the terminal device, and using the first video frame as a reference video frame, encoding the second to-be-encoded video frame in the initial video frame to obtain a second video frame, and finally transmitting the second video frame to the terminal device , for the terminal device to use the first video frame as a reference video frame to decode the second video frame, so that the mobile platform can adaptively adjust the encoding and compression ratio based on the channel bandwidth to reduce or increase the data volume of the transmitted video frame , in order to solve the problem that the transmitted video quality is degraded or the transmission is stuck, and ensure the reliability and video quality of wireless image transmission.

Please refer to FIG. 1. FIG. 1 is a schematic diagram of a scenario for implementing the video transmission method provided by the embodiment of the present application. As shown in FIG. 1, the scenario includes a movable platform 100 and a terminal device 200. The movable platform 100 includes a platform body 110, The power system 120 provided on the platform body 110, the photographing device 130 provided on the platform body, and the first wireless communication device (not shown in FIG. 1 ) provided in the platform body, the terminal device 200 includes a display device 210 and a first wireless communication device. Two wireless communication devices (not shown in FIG. 1 ), through which the first wireless communication device in the drone 100 can communicate with the second wireless communication device in the terminal device 200 , thereby establishing the communication between the drone 100 and the terminal device 200 The wireless channel between the mobile platform 100 and the terminal device 200 can be transmitted to the terminal device 200 through the wireless channel between the mobile platform 100 and the terminal device 200 after the initial video frame captured by the photographing device 130 is encoded.

The terminal device 200 displays the encoded video frame transmitted by the movable platform 100 through the display device 210 for the user to watch. It should be noted that the display device 210 includes a display screen disposed on the terminal device 200 or a display independent of the terminal device 200, and the display independent of the terminal device 200 may include a mobile phone, a tablet computer, a personal computer, etc. Other electronic equipment with a display screen. Among them, the display screen includes an LED display screen, an OLED display screen, an LCD display screen, and the like.

In one embodiment, the movable platform 100 may further include a pan-tilt 140 disposed on the platform body 110. The pan-tilt 140 is used for carrying the photographing device 130. The pan-tilt 140 includes three-axis motors, which are a pan-axis motor and a tilt-axis motor, respectively. The motor and the roll axis motor are used to adjust the balance posture of the photographing device 130 mounted on the pan/tilt 420, so as to photograph high-precision and stable images anytime and anywhere.

In one embodiment, the movable platform 100 may further include a sensing system, and the sensing system may include one or more sensors to sense the spatial orientation, velocity, and/or acceleration of the movable platform 100 (eg, relative to multiple sensors). up to three degrees of freedom of rotation and translation), angular acceleration, attitude, position (absolute position or relative position), etc. The one or more sensors include GPS sensors, motion sensors, inertial sensors, proximity sensors, or image sensors. Optionally, the sensing system may also be used to collect data on the environment in which the movable platform 100 is located, such as climatic conditions, potential obstacles to be approached, locations of geographic features, locations of man-made structures, and the like.

Wherein, the power system 120 is used to provide moving power for the movable platform 100, one or more of the power systems 120 in the horizontal direction can be rotated clockwise, and one or more of the other power systems 120 in the horizontal direction can be reversed Clockwise rotation. For example, there are as many power systems 120 rotating clockwise as there are power systems 120 rotating counterclockwise. The rotational rate of the power systems 120 in each horizontal direction can be varied independently to achieve the lifting and/or pushing operations caused by each power system 120 to adjust the spatial orientation, velocity, and/or acceleration of the movable platform 100 (eg, relative to up to three degrees of freedom for rotation and translation).

In one embodiment, the terminal device 100 includes a remote control, a ground control platform, a mobile phone, a tablet computer, a notebook computer, a PC computer, and the like. The movable platform can be a handheld mobile device, or a device that has a power system and moves with the power provided by the power system. Examples of mobile platforms include drones, unmanned boats, and unmanned vehicles. Therefore, the power system 120 enables the drone to take off vertically from the ground, or to land vertically on the ground, without any horizontal movement of the drone (eg, without taxiing on a runway). Optionally, the power system 120 may allow the drone to preset positions and/or turn the steering wheel in the air. One or more of the powertrains 120 may be controlled independently of the other powertrains 120 . Alternatively, one or more power systems 120 may be controlled simultaneously. For example, the drone may have multiple horizontally oriented power systems 120 to track the lift and/or push of the target. The horizontally oriented power system 120 may be actuated to provide the drone with the ability to take off vertically, land vertically, and hover.

In one embodiment, the movable platform 100 further includes a video transmission device (not shown in FIG. 1 ), through which the video transmission device can adjust the channel bandwidth of the wireless channel between the movable platform 100 and the terminal device 200 according to the channel bandwidth. The first encoding and compression ratio of the first type of video frame; according to the adjusted first encoding and compression ratio, encode the first to-be-encoded video frame in the initial video frame captured by the photographing device 130 to obtain the first video frame, and The first video frame is transmitted to the terminal device; the first video frame is used as a reference video frame, and the second to-be-encoded video frame in the initial video frame is encoded to obtain a second video frame; the second video frame is transmitted to The terminal device is used for the terminal device to use the first video frame as a reference video frame to decode the second video frame, so that the movable platform 100 can adaptively adjust the encoding and compression ratio based on the channel bandwidth, so as to reduce the Or increase the data volume of the transmitted video frame to solve the problem of the degradation of the transmitted video quality or the transmission freeze, and to ensure the reliability and video quality of the wireless image transmission.

Hereinafter, the video transmission method provided by the embodiments of the present application will be described in detail with reference to the scene in FIG. 1 . It should be noted that the scene in FIG. 1 is only used to explain the video transmission method provided by the embodiment of the present application, but does not constitute a limitation on the application scene of the video transmission method provided by the embodiment of the present application.

Please refer to FIG. 2. FIG. 2 is a schematic flowchart of steps of a video transmission method provided by an embodiment of the present application. It is applied to the mobile platform to solve the problem that the transmitted video quality is degraded or the transmission is stuck, and ensure the reliability and video quality of wireless image transmission.

As shown in FIG. 2, the video transmission method includes steps S101 to S104.

Step S101 , adjusting the first encoding and compression ratio of the first type of video frame according to the channel bandwidth of the wireless channel.

Wherein, the movable platform includes a photographing device, which can be mounted on the platform of the movable platform, or can be integrated with the movable platform. Through the photographing device, the environment where the movable platform is located can be photographed to obtain the initial The video frame, the initial video frame captured by the shooting device can be transmitted to the terminal device through the wireless channel between the movable platform and the terminal device after being encoded, and the initial video frame is encoded to obtain the first type of video frame or the second type of video frame. For video frames, the first type of video frames includes I frames, and the second type of video frames includes P frames. The initial video frame may be a single video frame, or may be a frame sequence composed of multiple video frames, which is not specifically limited in this embodiment of the present application.

In an embodiment, according to the channel bandwidth of the wireless channel between the movable platform and the terminal device, the manner of adjusting the first coding and compression ratio of the first type of video frame may be: When the channel bandwidth of the channel is less than the preset channel bandwidth, according to the channel bandwidth of the wireless channel between the mobile platform and the terminal device, the first coding and compression ratio of the first type of video frame is increased; When the channel bandwidth of the wireless channel between the mobile platform and the terminal device is greater than or equal to the preset channel bandwidth, and the first coding compression ratio is greater than the preset coding compression ratio, according to the channel bandwidth of the wireless channel between the mobile platform and the terminal device, reduce the first type The first encoding compression ratio of the video frame. The preset channel bandwidth and the preset coding compression ratio may be set based on actual conditions, which are not specifically limited in this embodiment of the present application.

When the distance between the mobile platform and the terminal device is long, the channel bandwidth of the wireless channel is less, and it is easy to occur that the terminal device requests the mobile platform for encoding to generate the first type of video frame, and the first type of video frame The corresponding amount of encoded data is large. When the channel bandwidth is lower than the preset channel bandwidth, the transmission of the first type of video frame with a large amount of encoded data through the wireless channel is likely to cause interruption of wireless image transmission. Therefore, when the channel bandwidth is lower than When the channel bandwidth is preset, the first encoding and compression ratio of the first type of video frame is increased, so that the first type of video frame is subsequently encoded by the increased first encoding and compression ratio, thereby reducing the encoding corresponding to the first type of video frame. The amount of data ensures the reliability of wireless image transmission.

After reducing the first encoding and compression ratio of the first type of video frame, when the channel bandwidth of the wireless channel between the mobile platform and the terminal device is greater than or equal to the preset channel bandwidth, if the first encoding and compression ratio after the reduction continues The first type of video frame is generated by encoding, although the reliability of wireless image transmission can be guaranteed, but the amount of encoded data corresponding to the first type of video frame is reduced, which will affect the quality of the video decoded by the terminal device. When the channel bandwidth of the wireless channel between the platform and the terminal device is greater than or equal to the preset channel bandwidth, and the first encoding and compression ratio is greater than the preset encoding and compression ratio, the first encoding and compression ratio of the first type of video frame is lowered so that the Subsequently, the first type of video frame is generated by encoding with the lowered first encoding and compression ratio, thereby increasing the amount of encoded data corresponding to the first type of video frame, which can improve the video decoded by the terminal device while ensuring the reliability of wireless image transmission. picture quality.

In an embodiment, according to the channel bandwidth of the wireless channel between the mobile platform and the terminal device, the manner of increasing or decreasing the first encoding and compression ratio of the first type of video frame may be: Compression ratio gain value; according to the compression ratio gain value, increase or decrease the first coding compression ratio of the first type of video frame, that is, add the first coding compression ratio to the compression ratio gain value to increase the first coding ratio compression ratio, or subtract the compression ratio gain value from the first coding compression ratio to lower the first coding compression ratio. Among them, the memory of the movable platform stores the mapping relationship between the channel bandwidth and the compression ratio gain value. Through the mapping relationship, the compression ratio gain value corresponding to the channel bandwidth, the channel bandwidth and the compression ratio gain value can be accurately obtained. The mapping relationship between them may be set based on the actual situation, which is not specifically limited in this embodiment of the present application.

In an embodiment, as shown in FIG. 3 , step S101 specifically includes: sub-steps S1011 to S1012.

Sub-step S1011, obtaining the complexity of the environment where the movable platform is located;

Sub-step S1012: Adjust the first coding compression ratio of the first type of video frame according to the channel bandwidth and the complexity of the wireless channel.

The complexity of the environment where the movable platform is located is determined according to the images or videos collected by the camera of the movable platform, and the complexity of the environment where the movable platform is located may be the spatial complexity of the images or videos collected by the camera. degree and/or time complexity, for example, obtaining the initial video frame captured by the camera, performing Sobel filtering on the initial video frame, and then calculating the standard deviation or variance of each pixel in the filtered initial video frame, and The complexity of the environment in which the movable platform is located is determined from the standard deviation or variance of each pixel in the filtered initial video frame.

In an embodiment, according to the channel bandwidth of the wireless channel between the movable platform and the terminal device and the complexity of the environment where the movable platform is located, the manner of adjusting the first encoding and compression ratio of the first type of video frame may be: When the channel bandwidth of the wireless channel between the movable platform and the terminal device is smaller than the preset channel bandwidth, and the complexity of the environment where the movable platform is located is smaller than the preset complexity, the first coding compression ratio is increased; When the channel bandwidth of the wireless channel between the platform and the terminal device is greater than or equal to the preset channel bandwidth, and the complexity of the environment where the movable platform is located is greater than or equal to the preset complexity, the first encoding and compression ratio is lowered. The preset complexity may be set based on an actual situation, which is not specifically limited in this embodiment of the present application.

When the distance between the mobile platform and the terminal device is long, the channel bandwidth of the wireless channel is less, and it is easy to occur that the terminal device requests the mobile platform for encoding to generate the first type of video frame, and the first type of video frame The corresponding amount of encoded data is large. When the channel bandwidth is lower than the preset channel bandwidth, the transmission of the first type of video frame with a large amount of encoded data through the wireless channel is likely to cause interruption of wireless image transmission. Therefore, when the channel bandwidth is lower than When the channel bandwidth is preset and the complexity of the scene is less than the preset complexity, the first encoding and compression ratio of the first type of video frame can be increased, so that the first type of video can be subsequently encoded by the increased first encoding and compression ratio. frame to reduce the amount of encoded data corresponding to the first type of video frame. Since the complexity of the scene is less than the preset complexity, the quality requirements of the video decoded by the terminal device are lower, so although the first type of video frame is reduced. The amount of encoded data corresponding to the video frame reduces the quality of the video decoded by the terminal device, but it can meet the needs of the current scene and ensure the reliability of wireless image transmission, which greatly improves the user experience.

After reducing the first encoding and compression ratio of the first type of video frame, when the channel bandwidth of the wireless channel between the mobile platform and the terminal device is greater than or equal to the preset channel bandwidth, if the first encoding and compression ratio after the reduction continues The first type of video frame is generated by encoding, although the reliability of wireless image transmission can be guaranteed, but the amount of encoded data corresponding to the first type of video frame is reduced, which will affect the quality of the video decoded by the terminal device. When the degree of complexity is greater than or equal to the preset complexity, the image quality of the video decoded by the terminal device is relatively high. Therefore, the channel bandwidth of the wireless channel between the mobile platform and the terminal device is greater than or equal to the preset channel bandwidth. And when the complexity of the scene is greater than or equal to the preset complexity, the first encoding and compression ratio of the first type of video frame is lowered, so that the first type of video frame is subsequently generated by encoding with the lowered first encoding and compression ratio, thereby increasing the number of video frames. The amount of encoded data corresponding to the first type of video frame can improve the image quality of the video decoded by the terminal device while ensuring the reliability of wireless image transmission, so that the image quality of the video decoded by the terminal device can meet the image quality of the current scene. quality needs.

In one embodiment, when the channel bandwidth of the wireless channel between the movable platform and the terminal device is less than the preset channel bandwidth, and the complexity of the scene is greater than or equal to the preset complexity, although the current scene has higher image quality requirements , but since the channel bandwidth is less than the preset channel bandwidth, if the amount of encoded data corresponding to the first type of video frame is not reduced, the wireless image transmission will be interrupted. Therefore, the channel bandwidth of the wireless channel between the mobile platform and the terminal device is less than When the channel bandwidth is preset and the complexity of the scene is greater than or equal to the preset complexity, the first encoding and compression ratio of the first type of video frame is increased, so that the first type of video is subsequently generated by encoding with the increased first encoding and compression ratio. frame to reduce the amount of encoded data corresponding to the first type of video frame and ensure the reliability of wireless image transmission.

In an embodiment, when the channel bandwidth of the wireless channel between the movable platform and the terminal device is greater than the preset channel bandwidth, and the complexity of the scene is less than the preset complexity, the first video frame of the first type of video frame is lowered by lowering the first channel bandwidth. Encoding compression ratio, so that the first type of video frame is subsequently generated by encoding with the lowered first encoding and compression ratio, thereby increasing the amount of encoded data corresponding to the first type of video frame, which can ensure the reliability of wireless image transmission and improve the terminal. The quality of the video decoded by the device.

Step S102: Encode the first to-be-encoded video frame in the initial video frame according to the adjusted first encoding and compression ratio to obtain a first video frame, and transmit the first video frame to the terminal equipment.

When the terminal device cannot decode the video frame transmitted by the mobile platform, the terminal device needs to send a first-type video frame generation request to the mobile platform, and when the mobile platform receives the first-type video frame sent by the terminal device. After the request is generated, the first video frame to be encoded in the initial video frame is encoded according to the adjusted first encoding and compression ratio to obtain the first video frame, and the first video frame is transmitted to the terminal device.

Wherein, the generation request of the first type of video frame carries the target frame sequence number, and the target frame sequence number includes the frame sequence number of the video frame that the terminal device needs to refer to when decoding the video or the frame sequence number of the video frame currently decoded by the terminal device. The sequence number can determine the first video frame to be encoded in the initial video frame. For example, if the target frame sequence number is the frame sequence number of the video frame that needs to be referenced when the terminal device decodes the video, then the initial video frame corresponding to the target frame sequence number is determined as The first video frame to be encoded, and if the target frame serial number is the frame serial number of the video frame currently decoded by the terminal device, subtract 1 from the target frame serial number to obtain the reference frame serial number, and determine the initial video frame corresponding to the reference frame serial number. is the first video frame to be encoded.

Step S103 , using the first video frame as a reference video frame, encode a second to-be-encoded video frame in the initial video frame to obtain a second video frame.

After the first video frame is sent to the terminal device, the first video frame is used as the reference video frame, and the second video frame to be encoded in the initial video frame is encoded to obtain the second video frame. Wherein, the frame sequence number difference between the first to-be-encoded video frame and the second to-be-encoded video frame is less than or equal to the preset frame sequence number difference, and the second to-be-encoded video frame may be determined according to the frame sequence number of the first video frame, for example , the frame sequence number of the first video frame is added by 1 to obtain the frame sequence number to be encoded, and the initial video frame corresponding to the to-be-encoded frame sequence number is determined as the second to-be-coded video frame. The preset frame sequence number difference can be set based on the actual situation, which is not specifically limited in this application.

Step S104: Transmit the second video frame to the terminal device, so that the terminal device uses the first video frame as a reference video frame to decode the second video frame.

After the second video frame is obtained by encoding, the second video frame is transmitted to the terminal device, and the terminal device receives the second video frame transmitted by the movable platform. Since the first video frame has been received before, and the second video frame is the first video frame A video frame is obtained by encoding for reference. Therefore, the terminal device uses the received first video frame as the reference video frame to decode the second video frame, so that the terminal device can display images.

The video transmission method provided by the above embodiment adjusts the first encoding and compression ratio of the first type of video frame through the channel bandwidth of the wireless channel between the movable platform and the terminal device, and then compares and shoots according to the adjusted first encoding and compression ratio. The first video frame to be encoded in the initial video frame captured by the device is encoded to obtain the first video frame, and the first video frame is transmitted to the terminal device, and the first video frame is used as the reference video frame, and the first video frame is used as the reference video frame. The second video frame to be encoded in the initial video frame is encoded to obtain a second video frame, and finally the second video frame is transmitted to the terminal device, so that the terminal device uses the first video frame as a reference video frame to Decoding, so that the mobile platform can adaptively adjust the encoding and compression ratio based on the channel bandwidth, so as to reduce or increase the data volume of the transmitted video frame, so as to solve the problem of the degradation of the transmitted video quality or the transmission freeze, and ensure the wireless image transmission. reliability and video quality.

Please refer to FIG. 4. FIG. 4 is a schematic flowchart of steps of another video transmission method provided by an embodiment of the present application.

As shown in FIG. 4 , the video transmission method includes steps S201 to S204.

Step S201, according to the channel bandwidth of the wireless channel, adjust the first encoding and compression ratio of the first type of video frame and the second encoding and compression ratio of the second type of video frame.

Wherein, the movable platform includes a photographing device, and the photographing device can be mounted on the platform of the movable platform, or can be integrated with the movable platform. Through the photographing device, the environment where the movable platform is located can be photographed to obtain the initial The video frame, the initial video frame captured by the shooting device can be transmitted to the terminal device through the wireless channel between the movable platform and the terminal device after being encoded. The amount of encoded data corresponding to the first type of video frame is greater than the amount of encoded data corresponding to the second type of video frame. The first type of video frame includes I frames, and the second type of video frame includes P frames.

It can be understood that, according to the channel bandwidth of the wireless channel, the first coding compression ratio and the second coding compression ratio can be lowered at the same time, the first coding compression ratio and the second coding compression ratio can also be raised at the same time, or the first coding compression ratio can be raised. One encoding compression ratio, and the second encoding compression ratio is lowered, the first encoding compression ratio may also be lowered, and the second encoding compression ratio is increased, which is not specifically limited in this embodiment of the present application.

In one embodiment, according to the channel bandwidth of the wireless channel between the mobile platform and the terminal device, the manner of adjusting the first encoding and compression ratio of the first type of video frame and the second encoding and compression ratio of the second type of video frame may be: : When the channel bandwidth of the wireless channel between the mobile platform and the terminal device is less than the preset channel bandwidth, increase the first encoding and compression ratio of the first type of video frame, and reduce the second encoding and compression ratio of the second type of video frame or, when the channel bandwidth of the wireless channel between the movable platform and the terminal device is greater than or equal to the preset channel bandwidth, and the first encoding and compression ratio is greater than the preset encoding and compression ratio, lower the number of the first type of video frame. A coding compression ratio is set, and the second coding compression ratio of the second type of video frame is increased. The preset channel bandwidth and the preset coding compression ratio may be set based on actual conditions, which are not specifically limited in this embodiment of the present application.

When the distance between the mobile platform and the terminal device is long, the channel bandwidth of the wireless channel is less, and it is easy to occur that the terminal device requests the mobile platform for encoding to generate the first type of video frame, and the first type of video frame The corresponding amount of encoded data is large. When the channel bandwidth is lower than the preset channel bandwidth, the transmission of the first type of video frame with a large amount of encoded data through the wireless channel is likely to cause interruption of wireless image transmission. Therefore, when the channel bandwidth is lower than When the channel bandwidth is preset, the first encoding and compression ratio of the first type of video frame is increased, so that the first type of video frame is subsequently encoded by the increased first encoding and compression ratio, thereby reducing the encoding corresponding to the first type of video frame. The amount of data ensures the reliability of wireless image transmission. In addition, by reducing the second encoding and compression ratio of the second type of video frame, the second type of video frame is subsequently generated by encoding with the reduced second encoding and compression ratio, thereby increasing the number of second type video frames. The amount of encoded data corresponding to the second type of video frame can quickly restore the image quality of the video decoded by the terminal device.

After reducing the first encoding and compression ratio of the first type of video frame, when the channel bandwidth of the wireless channel between the mobile platform and the terminal device is greater than or equal to the preset channel bandwidth, if the first encoding and compression ratio after the reduction continues The first type of video frame is generated by encoding, although the reliability of wireless image transmission can be guaranteed, but the amount of encoded data corresponding to the first type of video frame is reduced, which will affect the quality of the video decoded by the terminal device. When the channel bandwidth of the wireless channel between the platform and the terminal device is greater than or equal to the preset channel bandwidth, and the first encoding and compression ratio is greater than the preset encoding and compression ratio, the first encoding and compression ratio of the first type of video frame is lowered so that the Subsequently, the first type of video frame is generated by encoding with the lower first encoding and compression ratio, thereby increasing the amount of encoded data corresponding to the first type of video frame. In addition, by increasing the second encoding and compression ratio of the second type of video frame, the subsequent The second type of video frame is generated by increasing the second encoding and compression ratio, thereby reducing the amount of encoded data corresponding to the second type of video frame, which can ensure the reliability of wireless image transmission and improve the quality of the video decoded by the terminal device. image quality.

In an embodiment, as shown in FIG. 5 , step S201 may include: sub-steps S2011 to S2012.

Sub-step S2011, acquiring the complexity of the environment where the movable platform is located;

Sub-step S2012: Adjust the first coding compression ratio and the second coding compression ratio according to the channel bandwidth and the complexity of the wireless channel.

The complexity of the environment where the movable platform is located is determined according to the images or videos collected by the camera of the movable platform, and the complexity of the environment where the movable platform is located may be the spatial complexity of the images or videos collected by the camera. degree and/or time complexity.

It can be understood that, according to the channel bandwidth and complexity of the wireless channel, the first coding compression ratio and the second coding compression ratio can be lowered at the same time, or the first coding compression ratio and the second coding compression ratio can be raised at the same time, or When the first encoding compression ratio is increased and the second encoding compression ratio is decreased, the first encoding compression ratio can also be decreased while the second encoding compression ratio is increased, which is not specifically limited in this embodiment of the present application.

In one embodiment, according to the channel bandwidth of the wireless channel and the complexity of the environment in which the mobile platform is located, the method for adjusting the first coding compression ratio and the second coding compression ratio may be: the channel bandwidth of the wireless channel is smaller than the preset channel. bandwidth, and the complexity of the environment where the mobile platform is located is less than the preset complexity, increase the first coding compression ratio and lower the second coding compression ratio; or when the channel bandwidth of the wireless channel is greater than or equal to the preset channel bandwidth , and when the complexity of the environment in which the movable platform is located is greater than or equal to the preset complexity, the first encoding and compression ratio is lowered, and the second encoding and compression ratio is increased. The preset complexity may be set based on an actual situation, which is not specifically limited in this embodiment of the present application.

When the distance between the mobile platform and the terminal device is long, the channel bandwidth of the wireless channel is less, and it is easy to occur that the terminal device requests the mobile platform for encoding to generate the first type of video frame, and the first type of video frame The corresponding amount of encoded data is large. When the channel bandwidth is lower than the preset channel bandwidth, the transmission of the first type of video frame with a large amount of encoded data through the wireless channel is likely to cause interruption of wireless image transmission. Therefore, when the channel bandwidth is lower than When the channel bandwidth is preset and the complexity of the scene is less than the preset complexity, the first encoding and compression ratio of the first type of video frame can be increased to reduce the amount of encoded data corresponding to the first type of video frame, and then the amount of encoded data corresponding to the first type of video frame can be reduced. The method of sacrificing the image quality of the video decoded by the terminal device in time to ensure the effective transmission of key information, while reducing the second encoding compression ratio of the second type of video frame to increase the amount of encoded data corresponding to the second type of video frame, In this way, the image quality of the video decoded by the terminal device can be quickly restored, so that the image quality of the video decoded by the terminal device can meet the needs of the current scene, and can also ensure the reliability of wireless image transmission, which greatly improves the user experience.

After reducing the first encoding and compression ratio of the first type of video frame, when the channel bandwidth of the wireless channel between the mobile platform and the terminal device is greater than or equal to the preset channel bandwidth, if the first encoding and compression ratio after the reduction continues The first type of video frame is generated by encoding, although the reliability of wireless image transmission can be guaranteed, but the amount of encoded data corresponding to the first type of video frame is reduced, which will affect the quality of the video decoded by the terminal device. When the degree of complexity is greater than or equal to the preset complexity, the image quality of the video decoded by the terminal device is relatively high. Therefore, the channel bandwidth of the wireless channel between the mobile platform and the terminal device is greater than or equal to the preset channel bandwidth. And when the complexity of the scene is greater than or equal to the preset complexity, the first encoding and compression ratio of the first type of video frame can be lowered, so that the amount of encoded data corresponding to the first type of video frame can be restored to the initial state, and at the same time the first type of video frame can be increased. The second encoding and compression ratio of the second type of video frame can improve the image quality of the video decoded by the terminal device while ensuring the reliability of wireless image transmission, so that the image quality of the video decoded by the terminal device can meet the picture quality of the current scene. quality needs.

In one embodiment, when the channel bandwidth of the wireless channel between the movable platform and the terminal device is less than the preset channel bandwidth, and the complexity of the scene is greater than or equal to the preset complexity, although the current scene has higher image quality requirements , but since the channel bandwidth is smaller than the preset channel bandwidth, if the amount of encoded data corresponding to the first type of video frame is not reduced or increased, the wireless image transmission will be interrupted. Therefore, the channel of the wireless channel between the mobile platform and the terminal device When the bandwidth is less than the preset channel bandwidth, and the complexity of the scene is greater than or equal to the preset complexity, increase the first encoding and compression ratio of the first type of video frame to reduce the amount of encoded data corresponding to the first type of video frame and ensure wireless The reliability of image transmission, and at the same time appropriately increase the amount of encoded data of the second type of video frame to reduce the amount of encoded data corresponding to the second type of video. The image quality of the video can meet the image quality requirements of the current scene and improve the user experience.

In an embodiment, when the channel bandwidth of the wireless channel between the movable platform and the terminal device is greater than the preset channel bandwidth, and the complexity of the scene is less than the preset complexity, the first video frame of the first type of video frame is lowered by lowering the first channel bandwidth. The encoding compression ratio is used to increase the amount of encoded data corresponding to the first type of video frame. At the same time, by reducing the second encoding and compression ratio of the second type of video to increase the amount of encoded data corresponding to the second type of video frame, it is possible to ensure the wireless image quality. While improving the reliability of transmission, the image quality of the video decoded by the terminal device is improved.

Step S202: Encode the first to-be-encoded video frame in the initial video frame according to the adjusted first encoding and compression ratio to obtain a first video frame, and transmit the first video frame to the terminal equipment.

Step S203: Using the first video frame as a reference video frame, encode a second to-be-encoded video frame in the initial video frame according to the adjusted second encoding and compression ratio to obtain a second video frame.

After adjusting the second encoding and compression ratio and sending the first video frame to the terminal device, the first video frame is used as the reference video frame, and the second to-be-encoded video frame in the initial video frame is compared according to the adjusted second encoding and compression ratio Encoding is performed to obtain a second video frame, so as to adjust the amount of encoded data corresponding to the second video frame. Wherein, the frame sequence number difference between the first to-be-encoded video frame and the second to-be-encoded video frame is less than or equal to the preset frame sequence number difference, and the second to-be-encoded video frame may be determined according to the frame sequence number of the first video frame, for example , the frame sequence number of the first video frame is added by 1 to obtain the frame sequence number to be encoded, and the initial video frame corresponding to the to-be-encoded frame sequence number is determined as the second to-be-coded video frame. The preset frame sequence number difference can be set based on the actual situation, which is not specifically limited in this application.

Step S204: Transmit the second video frame to the terminal device, so that the terminal device uses the first video frame as a reference video frame to decode the second video frame.

In one embodiment, the target coding rate is determined according to the channel bandwidth of the wireless channel between the movable platform and the terminal device, and the current coding rate of the encoder of the movable platform is obtained; based on the target coding rate and the current coding The difference between the code rates controls the PID code stream controller in the movable platform to adjust the code rate of the encoder to the target code rate. Among them, the code flow control coefficients of the PID code flow controller include proportional control coefficients (P coefficients), integral control coefficients (I coefficients) and differential control coefficients (D coefficients). Through the proportional control coefficient (P coefficient), integral control coefficient (I coefficient) and differential control coefficient (D coefficient) of the PID code stream controller, based on the difference between the target coding rate and the current coding rate, the fast and smooth Adjusting the coding rate of the encoder to the target coding rate can avoid the influence of mutation and jitter of the coding rate on wireless image transmission.

In one embodiment, according to the channel bandwidth of the wireless channel, the method of determining the target coding code rate may be: obtaining a mapping relationship table between the channel bandwidth and the coding code rate; according to the mapping relationship table and the channel bandwidth of the wireless channel, determining Target encoding bit rate. The mapping relationship table between the channel bandwidth and the coding rate may be set based on the actual situation, which is not specifically limited in this embodiment of the present application.

In one embodiment, obtain the first frame sequence number of the video frame currently received by the terminal device fed back by the terminal device, and obtain the second frame sequence number of the video frame encoded by the encoder of the movable platform at the current moment; The frame serial number difference between the frame serial number and the second frame serial number is used to estimate the accumulated data volume of the wireless channel; when the accumulated data volume is greater than the preset data volume, the coding rate of the encoder of the movable platform is reduced, and the When the accumulated data volume is less than or equal to the preset data volume, no processing is performed. The preset data amount may be set based on the actual situation, which is not specifically limited in this embodiment of the present application. When the accumulated data amount of the wireless channel is greater than the preset data amount, the encoding bit rate of the encoder of the movable platform is reduced, so as to reduce the encoded data amount of the encoded video frame and reduce the load of the wireless channel.

In one embodiment, the method of reducing the encoding code rate of the encoder of the movable platform may be: according to the accumulated data amount, determine the code rate gain value; The current coding rate of the encoder of the movable platform is subtracted from the code rate gain value, so as to reduce the coding rate of the encoder of the movable platform. Among them, the memory of the movable platform stores the mapping relationship between the accumulated data amount and the code rate gain value. The larger the accumulated data amount, the larger the code rate gain value, and the smaller the accumulated data amount, the greater the code rate gain value. The code rate gain value can be quickly determined through the mapping relationship and the accumulated data amount, and the mapping relationship between the accumulated data amount and the code rate gain value can be set based on the actual situation, which is not specifically limited in this embodiment of the present application.

In an embodiment, the coding rate of the encoder of the movable platform may also be reduced according to a preset ratio. For example, if the preset ratio is 50%, the current encoding bit rate of the encoder of the movable platform is reduced to (100%-50%) of the current encoding bit rate. For another example, if the preset ratio is 30%, the available The current encoding rate of the encoder of the mobile platform is reduced to (100%-30%) of the current encoding rate. For another example, if the preset ratio is 25%, the current encoding rate of the encoder of the mobile platform is reduced to (100%-25%) of the current encoding bit rate.

In one embodiment, according to the frame sequence number difference between the first frame sequence number and the second frame sequence number, the method of estimating the accumulated data volume of the wireless channel may be: according to the current coding rate of the encoder, determine the unit of the video frame. Data volume: According to the unit data volume and the frame serial number difference between the first frame serial number and the second frame serial number, estimate the accumulated data volume of the wireless channel, that is, determine the product of the unit data volume and the frame serial number difference, and calculate the unit data volume. The product of the data amount and the frame number difference is determined as the accumulated data amount of the wireless channel. The memory of the movable platform stores the mapping relationship between the encoding bit rate and the unit data amount, and the unit data amount of the video frame can be determined through the mapping relationship and the current encoding bit rate of the encoder.

In one embodiment, a coding influence parameter is obtained, wherein the coding influence parameter includes the channel bandwidth of the wireless channel, the current system power consumption of the mobile platform, the complexity of the environment where the mobile platform is located, and/or the decoding capability of the terminal device ; According to the encoding influence parameter, adjust the encoding mode and video specification of the encoder of the mobile platform. The coding mode and video specification of the encoder of the movable platform are adaptively adjusted by coding influence parameters, so as to improve the battery life of the movable platform and ensure the transmission reliability and universality of wireless image transmission.

The video specification includes a first video specification and a second video specification, the first video specification includes Fullsize, the second video specification includes 2xbinning, the encoding mode includes a first encoding mode and a second encoding mode, and the encoding efficiency of the first encoding mode is greater than The encoding efficiency of the second encoding mode, the encoding mode further includes a third encoding mode, the first encoding mode includes High Efficiency Video Coding (HEVC), namely H.265/HEVC, and the second encoding mode includes Advanced Video Coding (Advanced Video Coding, AVC), namely H.264/AVC, the third encoding mode includes H.266/VVC. Compared with H.264/AVC, H.265/HEVC has a higher encoding compression ratio and a smaller amount of encoded data under the same image quality.

Exemplarily, if the decoding capability of the terminal device is that the terminal device only supports H.264/AVC and H.265/HEVC, adjust the encoding mode of the encoder of the mobile platform to H.264/AVC or H.265/ HEVC, and adjust the video specification of the encoder for the mobile platform to either Fullsize or 2xbinning. Through the decoding capability of the terminal device, the encoding mode and video specification of the encoder of the mobile platform can be adjusted adaptively, which can improve the universality of wireless image transmission.

Exemplarily, if the channel bandwidth of the wireless channel between the mobile platform and the terminal device is less than or equal to the preset channel bandwidth, adjust the encoding mode of the encoder of the mobile platform to the first encoding mode (H.265/HEVC). ), and adjust the video specification of the encoder of the movable platform to the second video specification (2xbinning); if the channel bandwidth of the wireless channel between the movable platform and the terminal device is greater than the preset channel bandwidth, the The encoding mode of the encoder is adjusted to any one of the first encoding mode (H.265/HEVC) and the second encoding mode (H.264/AVC), and the video specification of the encoder is adjusted to the first video specification ( Fullsize) and the second video specification (2xbinning). Through the channel bandwidth of the wireless channel, the encoding mode and video specification of the encoder of the mobile platform can be adjusted adaptively, which can take into account the reliability and image quality requirements of wireless image transmission.

Exemplarily, if the channel bandwidth of the wireless channel between the movable platform and the terminal device is less than or equal to the preset channel bandwidth, and the current system power consumption of the movable platform is less than the preset power consumption, the encoder of the movable platform is The encoding mode of the mobile platform is adjusted to the first encoding mode (H.265/HEVC), and the video specification of the encoder of the mobile platform is adjusted to the first video specification (Fullsize). If the wireless channel between the mobile platform and the terminal device The channel bandwidth of the mobile platform is less than or equal to the preset channel bandwidth, and the current system power consumption of the mobile platform is greater than or equal to the preset power consumption, then adjust the encoding mode of the encoder of the mobile platform to the first encoding mode (H.265/ HEVC), and adjust the video specification of the encoder of the mobile platform to the second video specification (2xbinning). According to the channel bandwidth of the wireless channel and the system power consumption of the mobile platform, the encoding mode and video specification of the encoder of the mobile platform can be adjusted adaptively, which can take into account the reliability of wireless image transmission, image quality requirements and the battery life of the mobile platform. .

Exemplarily, if the channel bandwidth of the wireless channel between the movable platform and the terminal device is greater than or equal to the preset channel bandwidth, and the current system power consumption of the movable platform is less than the preset power consumption, the encoder of the movable platform The encoding mode of the mobile platform is adjusted to the first encoding mode (H.265/HEVC), and the video specification of the encoder of the mobile platform is adjusted to the first video specification (Fullsize). If the wireless channel between the mobile platform and the terminal device The channel bandwidth of the mobile platform is greater than or equal to the preset channel bandwidth, and the current system power consumption of the mobile platform is greater than or equal to the preset power consumption, adjust the encoding mode of the encoder of the mobile platform to the second encoding mode (H.264/AVC ), and adjust the video specification of the encoder of the mobile platform to the second video specification (2xbinning). According to the channel bandwidth of the wireless channel and the system power consumption of the mobile platform, the encoding mode and video specification of the encoder of the mobile platform can be adjusted adaptively, which can take into account the reliability of wireless image transmission, image quality requirements and the battery life of the mobile platform. .

It can be understood that the coding mode and video specification of the encoder of the movable platform can also be adaptively adjusted according to the complexity of the environment in which the movable platform is located, which can improve the universality of wireless image transmission; The system power consumption adaptively adjusts the encoding mode and video specification of the encoder of the mobile platform, which can improve the battery life of the mobile platform; it can also adaptively adjust the mobile platform according to the complexity and channel bandwidth of the environment where the mobile platform is located. The encoding mode and video specification of the encoder can be used to take into account the reliability, image quality requirements and usage scenarios of wireless image transmission; it can also be determined by the channel bandwidth, the current system power consumption of the mobile platform and the complexity of the environment in which the mobile platform is located. , adaptively adjust the encoding mode and video specifications of the encoder of the mobile platform to take into account the reliability of wireless image transmission, image quality requirements, usage scenarios and the battery life of the mobile platform; System power consumption, the complexity of the environment where the mobile platform is located, and the decoding capability of the terminal device, adaptively adjust the encoding mode and video specifications of the encoder of the mobile platform to take into account the reliability of wireless image transmission, image quality requirements, use Battery life of scenes and movable platforms.

In the video transmission method provided by the above embodiment, the first encoding and compression ratio of the first type of video frame and the second encoding and compression ratio of the second type of video frame are adjusted through the channel bandwidth of the wireless channel between the movable platform and the terminal device, then encoding the first to-be-encoded video frame in the initial video frame captured by the photographing device according to the adjusted first encoding and compression ratio to obtain the first video frame, and transmitting the first video frame to the terminal device, and Using the first video frame as a reference video frame, encode the second to-be-encoded video frame in the initial video frame according to the adjusted second encoding and compression ratio to obtain a second video frame, and finally transmit the second video frame to the terminal A device for the terminal device to use the first video frame as a reference video frame to decode the second video frame, so that the mobile platform can adaptively adjust the encoding and compression ratio based on the channel bandwidth to reduce or increase the data of the transmitted video frame. In order to solve the problem of video quality degradation or transmission freeze, and ensure the reliability and video quality of wireless video transmission.

Please refer to FIG. 6. FIG. 6 is a schematic structural block diagram of a video transmission apparatus provided by an embodiment of the present application.

As shown in FIG. 6 , the video transmission device 300 includes a processor 301 and a memory 302, and the processor 301 and the memory 302 are connected by a bus 303, such as an I2C (Inter-integrated Circuit) bus. The video transmission device 300 is applied to a movable platform. The movable platform includes a shooting device. After encoding, the initial video frame captured by the shooting device can be transmitted to the terminal device through a wireless channel between the movable platform and the terminal device.

Specifically, the processor 301 may be a micro-controller unit (Micro-controller Unit, MCU), a central processing unit (Central Processing Unit, CPU), or a digital signal processor (Digital Signal Processor, DSP) or the like.

Specifically, the memory 302 may be a Flash chip, a read-only memory (ROM, Read-Only Memory) magnetic disk, an optical disk, a U disk, a mobile hard disk, and the like.

Wherein, the processor 301 is used for running the computer program stored in the memory 302, and implements the following steps when executing the computer program:

In an embodiment, the frame sequence number difference between the first to-be-encoded video frame and the second to-be-encoded video frame is less than or equal to a preset frame sequence number difference.

In an embodiment, the adjusting the first coding and compression ratio of the first type of video frame according to the channel bandwidth of the wireless channel includes:

When the channel bandwidth is smaller than the preset channel bandwidth, increasing the first coding compression ratio according to the channel bandwidth;

or

When the channel bandwidth is greater than or equal to a preset channel bandwidth, and the first encoding and compression ratio is greater than a preset encoding and compression ratio, the first encoding and compression ratio is lowered according to the channel bandwidth.

In an embodiment, the increasing the first coding compression ratio according to the channel bandwidth includes:

obtaining a compression ratio gain value corresponding to the channel bandwidth;

According to the compression ratio gain value, the first encoding compression ratio is increased.

obtaining the complexity of the environment in which the movable platform is located;

According to the channel bandwidth and the complexity of the wireless channel, the first coding compression ratio of the first type of video frame is adjusted.

In one embodiment, the complexity of the environment in which the movable platform is located is determined according to images or videos collected by the photographing device.

In an embodiment, the adjusting the first coding and compression ratio of the first type of video frame according to the channel bandwidth and the complexity of the wireless channel includes:

When the channel bandwidth is less than a preset channel bandwidth, and the complexity is less than a preset complexity, increasing the first coding compression ratio;

or

When the channel bandwidth is greater than or equal to a preset channel bandwidth, and the complexity is greater than or equal to a preset complexity, the first encoding and compression ratio is lowered.

According to the channel bandwidth of the wireless channel, adjusting the first encoding and compression ratio of the first type of video frame and the second encoding and compression ratio of the second type of video frame;

The said first video frame is used as a reference video frame, and the second to-be-encoded video frame in the initial video frame is encoded to obtain a second video frame, including:

Taking the first video frame as a reference video frame, encoding a second to-be-encoded video frame in the initial video frame according to the adjusted second encoding and compression ratio to obtain a second video frame.

In one embodiment, the amount of encoded data corresponding to the first type of video frame is greater than the amount of encoded data corresponding to the second type of video frame.

In one embodiment, the first type of video frames includes I-frames, and the second type of video frames includes P-frames.

In an embodiment, the adjusting the first encoding and compression ratio of the first type of video frame and the second encoding and compression ratio of the second type of video frame according to the channel bandwidth of the wireless channel includes:

When the channel bandwidth is smaller than the preset channel bandwidth, increasing the first coding compression ratio and decreasing the second coding compression ratio;

or

When the channel bandwidth is greater than or equal to a preset channel bandwidth, and the first encoding and compression ratio is greater than a preset encoding and compression ratio, the first encoding and compression ratio is lowered, and the second encoding and compression ratio is increased.

The first coding compression ratio and the second coding compression ratio are adjusted according to the channel bandwidth and the complexity of the wireless channel.

In an embodiment, the adjusting the first coding compression ratio and the second coding compression ratio according to the channel bandwidth and the complexity of the wireless channel includes:

When the channel bandwidth is smaller than the preset channel bandwidth and the complexity is smaller than the preset complexity, increasing the first coding compression ratio and decreasing the second coding compression ratio;

or

When the channel bandwidth is greater than or equal to a preset channel bandwidth, and the complexity is greater than or equal to a preset complexity, the first encoding and compression ratio is decreased, and the second encoding and compression ratio is increased.

In one embodiment, the processor is further configured to implement the following steps:

Determine the target coding rate according to the channel bandwidth of the wireless channel, and obtain the current coding rate of the encoder of the movable platform;

Based on the difference between the target encoding rate and the current encoding rate, the PID stream controller in the movable platform is controlled to adjust the encoding rate of the encoder to the target encoding rate Rate.

In an embodiment, the determining the target coding rate according to the channel bandwidth of the wireless channel includes:

Obtain the mapping table between channel bandwidth and coding rate;

The target coding code rate is determined according to the mapping relationship table and the channel bandwidth of the wireless channel.

Obtain the first frame sequence number of the video frame currently received by the terminal device fed back by the terminal device, and obtain the second frame sequence number of the video frame encoded by the encoder of the movable platform at the current moment;

Estimating the accumulated data amount of the wireless channel according to the frame sequence number difference between the first frame sequence number and the second frame sequence number;

When the accumulated data amount is greater than the preset data amount, the encoding code rate of the encoder of the movable platform is reduced.

In one embodiment, the reducing the coding rate of the encoder of the movable platform includes:

According to the accumulated data amount, determine the code rate gain value;

According to the code rate gain value, the code rate of the encoder of the movable platform is reduced.

In an embodiment, the estimating the accumulated data amount of the wireless channel according to the frame sequence number difference between the first frame sequence number and the second frame sequence number includes:

According to the current encoding bit rate of the encoder, determine the unit data amount of the video frame;

According to the unit data amount and the frame number difference between the first frame number and the second frame number, the accumulated data volume of the wireless channel is estimated.

Acquiring coding impact parameters, the coding impact parameters include the channel bandwidth, the current system power consumption of the mobile platform, the complexity of the environment where the mobile platform is located and/or the decoding capability of the terminal device;

According to the encoding influence parameter, the encoding mode and video specification of the encoder of the movable platform are adjusted.

In one embodiment, the encoding mode includes a first encoding mode and a second encoding mode, and the encoding efficiency of the first encoding mode is greater than the encoding efficiency of the second encoding mode.

It should be noted that those skilled in the art can clearly understand that, for the convenience and brevity of the description, for the specific working process of the video transmission device described above, reference may be made to the corresponding process in the foregoing video transmission method embodiment, which is not described here. Repeat.

Please refer to FIG. 7. FIG. 7 is a schematic structural block diagram of a movable platform provided by an embodiment of the present application.

As shown in FIG. 7 , the movable platform 400 includes a platform body 410 , a power system 420 , a photographing device 430 and a video transmission device 440 . In order to provide moving power for the movable platform 400, the shooting device 430 is used for initial video frame, and the video transmission device 440 is used for encoding the initial video frame captured by the shooting device 430 and for transmitting the encoded initial video frame to the terminal. Equipment, the video transmission device 440 is also used to control the movement of the movable platform.

It should be noted that those skilled in the art can clearly understand that, for the convenience and brevity of the description, for the specific working process of the movable platform described above, reference may be made to the corresponding process in the foregoing video transmission method embodiment, which is not described here. Repeat.

Embodiments of the present application further provide a computer-readable storage medium, where a computer program is stored in the computer-readable storage medium, and the computer program includes program instructions, and the processor executes the program instructions to realize the provision of the above embodiments. The steps of the video transmission method.

The computer-readable storage medium may be an internal storage unit of the removable platform described in any of the foregoing embodiments, such as a hard disk or a memory of the removable platform. The computer-readable storage medium can also be an external storage device of the removable platform, such as a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital) equipped on the removable platform , SD) card, flash memory card (Flash Card), etc.

It should be understood that the terms used in the specification of the present application herein are for the purpose of describing particular embodiments only and are not intended to limit the present application. As used in this specification and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural unless the context clearly dictates otherwise.

It will also be understood that, as used in this specification and the appended claims, the term "and/or" refers to and including any and all possible combinations of one or more of the associated listed items.

The above are only specific embodiments of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of various equivalents within the technical scope disclosed in the present application. Modifications or substitutions shall be covered by the protection scope of this application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

A video transmission method, characterized in that it is applied to a movable platform, the movable platform includes a photographing device, and the initial video frame photographed by the photographing device can pass through the communication between the movable platform and the terminal device after being encoded. The wireless channel is transmitted to the terminal device, and the method includes:

adjusting the first coding compression ratio of the first type of video frame according to the channel bandwidth of the wireless channel;

Encode the first to-be-encoded video frame in the initial video frame according to the adjusted first encoding and compression ratio to obtain a first video frame, and transmit the first video frame to the terminal device;

Taking the first video frame as a reference video frame, encoding the second to-be-encoded video frame in the initial video frame to obtain a second video frame;

The second video frame is transmitted to the terminal device, so that the terminal device uses the first video frame as a reference video frame to decode the second video frame.
The video transmission method according to claim 1, wherein the frame number difference between the first to-be-encoded video frame and the second to-be-encoded video frame is less than or equal to a preset frame number difference.
The video transmission method according to claim 1, wherein the adjusting the first coding and compression ratio of the first type of video frame according to the channel bandwidth of the wireless channel comprises:

When the channel bandwidth is smaller than the preset channel bandwidth, increasing the first coding compression ratio according to the channel bandwidth;

or

When the channel bandwidth is greater than or equal to a preset channel bandwidth, and the first encoding and compression ratio is greater than a preset encoding and compression ratio, the first encoding and compression ratio is lowered according to the channel bandwidth.
The video transmission method according to claim 3, wherein the increasing the first encoding and compression ratio according to the channel bandwidth comprises:

obtaining a compression ratio gain value corresponding to the channel bandwidth;

According to the compression ratio gain value, the first encoding compression ratio is increased.
The video transmission method according to claim 1, wherein the adjusting the first coding and compression ratio of the first type of video frame according to the channel bandwidth of the wireless channel comprises:

obtaining the complexity of the environment in which the movable platform is located;

According to the channel bandwidth and the complexity of the wireless channel, the first coding compression ratio of the first type of video frame is adjusted.
The video transmission method according to claim 5, wherein the complexity of the environment where the movable platform is located is determined according to the images or videos collected by the photographing device.
The video transmission method according to claim 5, wherein the adjusting the first coding and compression ratio of the first type of video frame according to the channel bandwidth and the complexity of the wireless channel comprises:

When the channel bandwidth is less than a preset channel bandwidth, and the complexity is less than a preset complexity, increasing the first coding compression ratio;

or

When the channel bandwidth is greater than or equal to a preset channel bandwidth, and the complexity is greater than or equal to a preset complexity, the first encoding and compression ratio is lowered.
The video transmission method according to claim 1, wherein the adjusting the first coding and compression ratio of the first type of video frame according to the channel bandwidth of the wireless channel comprises:

According to the channel bandwidth of the wireless channel, adjusting the first encoding and compression ratio of the first type of video frame and the second encoding and compression ratio of the second type of video frame;

The said first video frame is used as a reference video frame, and the second to-be-encoded video frame in the initial video frame is encoded to obtain a second video frame, including:

Taking the first video frame as a reference video frame, encoding a second to-be-encoded video frame in the initial video frame according to the adjusted second encoding and compression ratio to obtain a second video frame.
The video transmission method according to claim 8, wherein the amount of encoded data corresponding to the first type of video frame is greater than the amount of encoded data corresponding to the second type of video frame.
The video transmission method according to claim 8, wherein the video frames of the first type include I frames, and the video frames of the second type include P frames.
The video transmission method according to claim 8, wherein the first coding and compression ratio of the first type of video frame and the second coding and compression ratio of the second type of video frame are adjusted according to the channel bandwidth of the wireless channel. ,include:

When the channel bandwidth is smaller than the preset channel bandwidth, increasing the first coding compression ratio and decreasing the second coding compression ratio;

or

When the channel bandwidth is greater than or equal to a preset channel bandwidth, and the first encoding and compression ratio is greater than a preset encoding and compression ratio, the first encoding and compression ratio is lowered, and the second encoding and compression ratio is increased.
The video transmission method according to claim 8, wherein the first coding and compression ratio of the first type of video frame and the second coding and compression ratio of the second type of video frame are adjusted according to the channel bandwidth of the wireless channel. ,include:

obtaining the complexity of the environment in which the movable platform is located;

The first coding compression ratio and the second coding compression ratio are adjusted according to the channel bandwidth and the complexity of the wireless channel.
The video transmission method according to claim 12, wherein the adjusting the first coding compression ratio and the second coding compression ratio according to the channel bandwidth and the complexity of the wireless channel comprises:

When the channel bandwidth is smaller than the preset channel bandwidth and the complexity is smaller than the preset complexity, increasing the first coding compression ratio and decreasing the second coding compression ratio;

or

When the channel bandwidth is greater than or equal to a preset channel bandwidth, and the complexity is greater than or equal to a preset complexity, the first encoding and compression ratio is decreased, and the second encoding and compression ratio is increased.
The video transmission method according to any one of claims 1-13, wherein the method further comprises:

Determine the target coding rate according to the channel bandwidth of the wireless channel, and obtain the current coding rate of the encoder of the movable platform;

Based on the difference between the target encoding rate and the current encoding rate, the PID stream controller in the movable platform is controlled to adjust the encoding rate of the encoder to the target encoding rate Rate.
The video transmission method according to claim 14, wherein the determining the target coding rate according to the channel bandwidth of the wireless channel comprises:

Obtain the mapping table between channel bandwidth and coding rate;

The target coding code rate is determined according to the mapping relationship table and the channel bandwidth of the wireless channel.
The video transmission method according to any one of claims 1-13, wherein the method further comprises:

Obtain the first frame sequence number of the video frame currently received by the terminal device fed back by the terminal device, and obtain the second frame sequence number of the video frame encoded by the encoder of the movable platform at the current moment;

According to the frame sequence number difference between the first frame sequence number and the second frame sequence number, estimate the accumulated data amount of the wireless channel;

When the accumulated data amount is greater than the preset data amount, the encoding code rate of the encoder of the movable platform is reduced.
The video transmission method according to claim 16, wherein the reducing the coding rate of the encoder of the movable platform comprises:

According to the accumulated data amount, determine the code rate gain value;

According to the code rate gain value, the code rate of the encoder of the movable platform is reduced.
The video transmission method according to claim 16, wherein the estimating the accumulated data volume of the wireless channel according to the frame sequence number difference between the first frame sequence number and the second frame sequence number comprises the following steps: :

According to the current encoding bit rate of the encoder, determine the unit data amount of the video frame;

According to the unit data amount and the frame number difference between the first frame number and the second frame number, the accumulated data volume of the wireless channel is estimated.
The video transmission method according to any one of claims 1-13, wherein the method further comprises:

Acquiring coding impact parameters, where the coding impact parameters include the channel bandwidth, the current system power consumption of the mobile platform, the complexity of the environment in which the mobile platform is located, and/or the decoding capability of the terminal device;

According to the encoding influence parameter, the encoding mode and video specification of the encoder of the movable platform are adjusted.
The video transmission method according to claim 19, wherein the encoding mode includes a first encoding mode and a second encoding mode, and the encoding efficiency of the first encoding mode is greater than the encoding efficiency of the second encoding mode.
A video transmission device is characterized in that it is applied to a movable platform, the movable platform includes a shooting device, and the initial video frame captured by the shooting device can pass through the communication between the movable platform and the terminal device after being encoded. the wireless channel is transmitted to the terminal device;

The video transmission device includes a memory and a processor;

the memory is used to store computer programs;

The processor is configured to execute the computer program and implement the following steps when executing the computer program:

According to the channel bandwidth of the wireless channel, adjust the first coding compression ratio of the first type of video frame;

Encode the first to-be-encoded video frame in the initial video frame according to the adjusted first encoding and compression ratio to obtain a first video frame, and transmit the first video frame to the terminal device;

Taking the first video frame as a reference video frame, encoding the second to-be-encoded video frame in the initial video frame to obtain a second video frame;

The second video frame is transmitted to the terminal device, so that the terminal device uses the first video frame as a reference video frame to decode the second video frame.
The video transmission apparatus according to claim 21, wherein a frame number difference between the first to-be-encoded video frame and the second to-be-encoded video frame is less than or equal to a preset frame number difference.
The video transmission device according to claim 21, wherein the adjusting the first coding and compression ratio of the first type of video frame according to the channel bandwidth of the wireless channel comprises:

When the channel bandwidth is smaller than the preset channel bandwidth, increasing the first coding compression ratio according to the channel bandwidth;

or

When the channel bandwidth is greater than or equal to a preset channel bandwidth, and the first encoding and compression ratio is greater than a preset encoding and compression ratio, the first encoding and compression ratio is lowered according to the channel bandwidth.
The video transmission apparatus according to claim 23, wherein the increasing the first encoding and compression ratio according to the channel bandwidth comprises:

obtaining a compression ratio gain value corresponding to the channel bandwidth;

According to the compression ratio gain value, the first encoding compression ratio is increased.
The video transmission apparatus according to claim 21, wherein the adjusting the first coding and compression ratio of the first type of video frame according to the channel bandwidth of the wireless channel comprises:

obtaining the complexity of the environment in which the movable platform is located;

According to the channel bandwidth and the complexity of the wireless channel, the first coding compression ratio of the first type of video frame is adjusted.
The video transmission device according to claim 25, wherein the complexity of the environment where the movable platform is located is determined according to the images or videos collected by the photographing device.
The video transmission device according to claim 25, wherein the adjusting the first coding and compression ratio of the first type of video frame according to the channel bandwidth and the complexity of the wireless channel comprises:

When the channel bandwidth is less than a preset channel bandwidth, and the complexity is less than a preset complexity, increasing the first coding compression ratio;

or

When the channel bandwidth is greater than or equal to a preset channel bandwidth, and the complexity is greater than or equal to a preset complexity, the first encoding and compression ratio is lowered.
The video transmission apparatus according to claim 21, wherein the adjusting the first coding and compression ratio of the first type of video frame according to the channel bandwidth of the wireless channel comprises:

According to the channel bandwidth of the wireless channel, adjusting the first encoding and compression ratio of the first type of video frame and the second encoding and compression ratio of the second type of video frame;

The said first video frame is used as a reference video frame, and the second to-be-encoded video frame in the initial video frame is encoded to obtain a second video frame, including:

Taking the first video frame as a reference video frame, encoding the second to-be-encoded video frame in the initial video frame according to the adjusted second encoding and compression ratio to obtain a second video frame.
The video transmission apparatus according to claim 28, wherein the amount of encoded data corresponding to the first type of video frame is greater than the amount of encoded data corresponding to the second type of video frame.
The video transmission apparatus according to claim 28, wherein the video frames of the first type include I frames, and the video frames of the second type include P frames.
The video transmission device according to claim 28, wherein the first coding and compression ratio of the first type of video frame and the second coding and compression ratio of the second type of video frame are adjusted according to the channel bandwidth of the wireless channel. ,include:

When the channel bandwidth is smaller than the preset channel bandwidth, increasing the first coding compression ratio and decreasing the second coding compression ratio;

or

When the channel bandwidth is greater than or equal to a preset channel bandwidth, and the first encoding and compression ratio is greater than a preset encoding and compression ratio, the first encoding and compression ratio is lowered, and the second encoding and compression ratio is increased.
The video transmission device according to claim 28, wherein the first coding and compression ratio of the first type of video frame and the second coding and compression ratio of the second type of video frame are adjusted according to the channel bandwidth of the wireless channel. ,include:

obtaining the complexity of the environment in which the movable platform is located;

The first coding compression ratio and the second coding compression ratio are adjusted according to the channel bandwidth and the complexity of the wireless channel.
The video transmission apparatus according to claim 32, wherein the adjusting the first coding and compression ratio and the second coding and compression ratio according to the channel bandwidth and the complexity of the wireless channel comprises:

When the channel bandwidth is smaller than the preset channel bandwidth and the complexity is smaller than the preset complexity, increasing the first coding compression ratio and decreasing the second coding compression ratio;

or

When the channel bandwidth is greater than or equal to a preset channel bandwidth, and the complexity is greater than or equal to a preset complexity, the first encoding and compression ratio is decreased, and the second encoding and compression ratio is increased.
The video transmission device according to any one of claims 21-33, wherein the processor is further configured to implement the following steps:

According to the channel bandwidth of the wireless channel, determine the target coding rate, and obtain the current coding rate of the encoder of the movable platform;

Based on the difference between the target encoding rate and the current encoding rate, the PID stream controller in the movable platform is controlled to adjust the encoding rate of the encoder to the target encoding rate Rate.
The video transmission apparatus according to claim 34, wherein the determining the target coding rate according to the channel bandwidth of the wireless channel comprises:

Obtain the mapping table between channel bandwidth and coding rate;

The target coding code rate is determined according to the mapping relationship table and the channel bandwidth of the wireless channel.
The video transmission device according to any one of claims 21-33, wherein the processor is further configured to implement the following steps:

Obtain the first frame sequence number of the video frame currently received by the terminal device fed back by the terminal device, and obtain the second frame sequence number of the video frame encoded by the encoder of the movable platform at the current moment;

Estimating the accumulated data amount of the wireless channel according to the frame sequence number difference between the first frame sequence number and the second frame sequence number;

When the accumulated data amount is greater than the preset data amount, the encoding code rate of the encoder of the movable platform is reduced.
The video transmission device according to claim 36, wherein the reducing the coding rate of the encoder of the movable platform comprises:

According to the accumulated data amount, determine the code rate gain value;

According to the code rate gain value, the code rate of the encoder of the movable platform is reduced.
The video transmission apparatus according to claim 36, wherein the estimating the accumulated data amount of the wireless channel according to the frame sequence number difference between the first frame sequence number and the second frame sequence number comprises the following steps: :

According to the current encoding bit rate of the encoder, determine the unit data amount of the video frame;

According to the unit data amount and the frame number difference between the first frame number and the second frame number, the accumulated data volume of the wireless channel is estimated.
The video transmission device according to any one of claims 21-33, wherein the processor is further configured to implement the following steps:

Acquiring coding impact parameters, where the coding impact parameters include the channel bandwidth, the current system power consumption of the mobile platform, the complexity of the environment where the mobile platform is located, and/or the decoding capability of the terminal device;

According to the encoding influence parameter, the encoding mode and video specification of the encoder of the movable platform are adjusted.
The video transmission apparatus according to claim 39, wherein the encoding mode includes a first encoding mode and a second encoding mode, and the encoding efficiency of the first encoding mode is greater than the encoding efficiency of the second encoding mode.
A movable platform is characterized in that, comprising:

Platform ontology;

a power system, arranged on the platform body, for providing moving power for the movable platform;

a photographing device, arranged on the platform body, for photographing an initial video frame;

The video transmission device according to any one of claims 21 to 40, provided in the platform body, for encoding the initial video frame captured by the photographing device and for encoding the encoded initial video frame transmitted to the terminal device.
A computer-readable storage medium, characterized in that, the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the processor implements the method described in any one of claims 1-20. The steps of the video transmission method described above.