JPH08214295A - Picture transmitter - Google Patents

Abstract

PURPOSE: To prevent a joint between scenes from being discontinued by automatically adjusting the total number of bits in a bit stream of each scene so that the total number of bits becomes multiple of the number of unit processing bits for a CPU or a multiple of the number of bits corresponding to the distance of a header. CONSTITUTION: After adding a bit string 34 of zero data to the end of a bit stream 30 so that the total number of bits in the bit stream 30 becomes a multiple of the number of bits corresponding to a distance D, the bit stream 30 is stored in a storage device. Thereby even at the time of continuing the bit streams of plural scenes, no fraction is generated in the number of unit processing bits for the CPU and no fraction is generated in the distances D of identifier H. In the case of connecting a bit stream 40 for a 2nd scene is connected to a 1st scene, the stream 40 is connected to the bit string 34 of zero data. In the case of connecting several scenes out of scenes stored in the storage device in an arbitrary order and reproducing and transmitting the connected scenes as one continued image/sound data, joints of the scenes are not discontinued.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image transmitting apparatus such as a transmitting apparatus or a receiving apparatus which compresses and encodes image data or image / sound data by a codec device and temporarily stores the data in a storage device. H. The present invention relates to an image transmission device that performs image processing conforming to H.261.

[0002]

2. Description of the Related Art As an example of an image transmitting apparatus which also serves as a recorder as one of image transmitting apparatuses, this type of image transmitting apparatus transmits an image by compressing and encoding video and audio of news or the like collected at the site. It is used in such a way that several scenes are stored in the internal storage device of the device and then transmitted to a remote place at a low transmission rate. However, when a picture taken at a compression rate of 1.5 Mbps is sent at a low transmission rate of 64 Kbps using the ISDN digital line network, it takes about 24 times as long as the picture taking time. In this way, transmission takes a long time and the line usage fee is expensive,
It is desirable that not all the shot scenes are transmitted, but only important scenes are selected and rough editing such as changing the order of the scenes can be performed and transmitted.

The video and audio taken into the image transmitting apparatus are processed by the built-in CPU for each unit processing bit number such as 8 bits or 16 bits.
However, H. Since the image compressed data conforming to the H.261 standard has a variable length coding algorithm in bit units, if the scene to be transmitted is simply extracted by the CPU processing, the total number of bits of the bit stream of the image compressed data of one scene becomes the CPU. The unit processing bit number is not a multiple, and a fraction often occurs at the end of the bit stream. If you connect to the next scene while leaving this fractional bit or simply deleting the fractional part bit, when you play it, the bitstream after that part cannot be read correctly, so the image after the seam It will be disturbed and collapse. Therefore, in the past, H.264. Two
When reproducing or transmitting image data compressed and encoded according to the 61 standard, the operation of reproduction and stop is repeated for each scene by hardware or software.

[0004]

However, in this case, since each scene is reset and played back, the image and sound become discontinuous at the time of switching the scene, and the image is stopped or the sound is lost. There was a problem with noise.

[0005]

According to the present invention, the total number of bits of the bit stream of each scene stored in a storage device is C
It is automatically adjusted so as to be a multiple of the unit processing bit number of the PU or the bit number of the interval of the identifier of the data content so that the seam between scenes does not become discontinuous. That is, according to the present invention, the H.264 format composed of a bitstream in which a PSC code is inserted at the beginning of a frame is used. The image data compressed and encoded according to the H.261 standard is
In an image transmission device that is temporarily stored in an internal storage device under U control, bits after the last PSC code of a bitstream of image data of one scene are deleted, and the total number of bitstreams is the unit processing bit of the CPU. A feature is that the bit of the zero data is added to the end of the bit stream until it becomes a multiple of the number, and then the image data is stored in the storage device. Further, according to the present invention, compression-coded audio data and a PSC at the beginning of a frame are used.
With the code inserted, An image transmission apparatus for temporarily storing, in the internal storage device, image / sound data composed of a bit stream mixed with image data compressed and encoded according to the H.261 standard and having data content identifiers inserted at predetermined intervals. And the number of bits in the identifier interval is C
In the image transmission device that is a multiple of the unit processing bit number of PU, the bits after the last PSC code of the bit stream of the image / audio data of one scene are deleted, and the total number of the bit stream is the number of bits in the interval of the identifier. It is characterized in that the bit of zero data is added to the end of the bit stream until the multiple becomes, and then the image / sound data is stored in the storage device.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below by taking an image transmitting device having a recording function as one of the image transmitting devices. FIG. 1 is a conceptual diagram showing an example of a bit stream 10 of compression-encoded image data of one scene,
It shows the tail portion of bitstream 10 immediately after being shredded by the hardware. In the bit stream 10, a PSC code 12 representing the start position of the frame is inserted at the beginning of each frame. The end of the bit stream 10 of one scene is cut off when the recording operation of the image data supplied from the video camera is stopped.

In the image transmitting apparatus according to the present invention, when such image data is input from a video camera or the like, the CPU is operated every time the end of the bit stream for each scene is determined by the operation of the hardware. Then, the bit stream is sequentially stored in the storage device after the following processing is performed. (1) Search for the last PSC code 12e and select this PSC
Delete bits after code 12e. (2) Bits of zero data are added to the end of the bitstream 10 until the total number of bitstreams 10 becomes a multiple of the number of unit processing bits of the CPU. That is, as shown in FIG. 2, a bit string 14 of zero data is added after the last bit in which the PSC code 12e was present. (3) The bit stream 10 of this image data is stored in the storage device. These processes may be performed before the image data is input from the video camera to the transmission device and before being stored in the storage device. Alternatively, only the bitstream may be read and rewritten.

In this way, the bit stream of each scene is stored in the storage device after its end is processed so as to be a multiple of the unit processing bit number of the CPU. As a result, since there is no fraction with respect to the unit processing bit number of the CPU, the data reading operation is performed correctly. P
The bit string 14 of zero data preceding the SC code does not adversely affect the image display. Therefore, if you select some of the necessary scenes from the scenes stored in the storage device, connect these scenes in any order, and play back or transmit as one continuous audiovisual data, The seams do not become discontinuous. In this example, as shown in FIG. 3, immediately after the bit string 14 of zero data of the bit stream 10 of the first scene,
The bitstream 20 of the second scene will be concatenated.

On the other hand, FIG. 4 shows an example of a bit stream 30 of image / audio data in which image data and audio data, both of which are compression-coded, are mixed. In the bit stream 30 of the image and audio data of one scene that has been compression-encoded,
A PSC code 32 indicating the beginning position of the frame is inserted, and an identifier H indicating the type of data content such as image, sound, control, etc. is inserted at a predetermined interval D. For the number of bits of the interval D, for example, the number of unit processing bits of the CPU is 8
In the case of bits, 512 bits (64 bytes) are selected so as to be a multiple of the unit processing bit number of the CPU. In the case of the bitstream 30 including such image and audio data, the number of bits of the bitstream 30 of each scene is processed by the CPU so as to be a multiple of the number of bits of the interval D of the identifier H.

Now, it is assumed that the unit processing bit number of the CPU is 8 bits and the bit number of the interval D is 512 bits. As shown in FIG. 4, when the end of the bit stream 30 is fragmented by hardware, the CPU searches for the last PSC code 32e and deletes the bits after this PSC code 32e. Then, a bit string 34 of zero data is added to the end so that the total number of bit streams 30 is a multiple of the number of bits of the interval D as shown in FIG. 5, and then the bit stream 30 is stored in the storage device. As a result, even when the bit streams of a plurality of scenes are connected, a fraction of the unit processing bit number of the CPU does not appear, and the interval D of the identifier H does not shift. The second after the bitstream 30 of the first scene
When the bitstream 40 of the scene is connected,
As shown in, the data is connected after the bit string 34 of zero data. Therefore, when some of the scenes stored in the storage device are connected in an arbitrary order to be reproduced and transmitted as a series of image / audio data, the seam between the scenes does not become discontinuous.

Although the example of the transmitting device has been described, the present invention can be applied not only to the transmitting device but also to the receiving device.
That is, H.264. With respect to the received image data that has been compressed and encoded according to the H.261 standard and the end of which has not been processed, the total number of bit streams of one scene becomes a multiple of the unit processing bit number of the CPU, or the interval D of the identifier H The image data may be stored in the storage device inside the receiving device after the bit of zero data is added to the end until it becomes a multiple of the number of bits. By doing this, when you select several scenes and rearrange them, or extract a part of each scene and edit it, and play it back as a series of image data, the seams between the scenes are discontinuous. Can be prevented.

[0012]

According to the present invention, the total number of bits of the bit stream of each scene is a multiple of the number of unit processing bits of the CPU or the number of bits of the interval D of the identifier H at the time of storing in the internal storage device. It is automatically adjusted to be a multiple of. Therefore, even if some necessary scenes are rearranged in an arbitrary order, edited into a series of image / audio data, reproduced, and transmitted, the seams between the scenes do not become discontinuous. Then, the images are smoothly connected without being stopped between the scenes, and the noise is not generated in the sound. The transmitting device to which the present invention is applied can save the trouble of editing again on the receiving side, and is therefore particularly useful for transmitting news materials that are in rush.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a bit stream of image data immediately after shredding.

FIG. 2 is a diagram showing the end of the same bitstream after inserting zero data.

FIG. 3 is a diagram showing a state in which a bitstream of another scene is connected to the end of the same.

FIG. 4 is a diagram showing a bit stream of other video and audio data immediately after the shredding.

FIG. 5 is a diagram showing the end of the same bitstream after inserting zero data.

FIG. 6 is a diagram showing a state in which a bitstream of another scene is connected to the end of the same.

[Explanation of symbols]

 H identifier D interval between identifiers 30 Bitstream of first scene 32 PSC code 32e Last PSC code 34 Inserted zero data bit string

Claims (2)

[Claims] 1. An H.264 format consisting of a bitstream in which a PSC code is inserted at the beginning of a frame. In an image transmission device in which image data compressed and encoded according to the H.261 standard is temporarily stored in an internal storage device under CPU control, bits after the last PSC code of the bit stream of image data of one scene are deleted. The configuration is such that zero image bits are added to the end of the bit stream until the total number of the bit streams becomes a multiple of the unit processing bit number of the CPU, and then the image data is stored in the storage device. Image transmission device. 2. The H.264 data with compression encoded voice data and a PSC code inserted at the beginning of a frame. An image transmission apparatus that temporarily stores, in the internal storage device, image and audio data that is a bit stream in which image data compressed and encoded according to the H.261 standard is mixed and identifiers of data contents are inserted at predetermined intervals. In the image transmission device in which the number of bits of the interval between the identifiers is a multiple of the unit processing bit number of the CPU, the bits after the last PSC code of the bit stream of the image / audio data of one scene are deleted, and the bit is deleted. It is characterized in that bits of zero data are added to the end of the bit stream until the total number of streams becomes a multiple of the number of bits of the interval of the identifier, and then the image / audio data is stored in the storage device. Image transmission device.