JP2004194026A - Moving image converter and moving image storage device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a moving image storage device capable of transmitting moving images easy to view for a user while reducing the load on a portable terminal. <P>SOLUTION: In the moving image storage device, power is fixedly secured, relatively high calculation capacity is held as well and images are changed suitably for a portable viewing device. Encoded data stored in a moving image storage part 102 are decoded / changed in a moving image changing part 104. Then, encoding is performed in a moving image encoding part 105 and the encoded data are transmitted from a moving image output part 106 to a portable viewing terminal. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a moving image storage device that stores moving image data and transmits the moving image data to a portable viewing terminal of a user, and a moving image distribution system suitable for using the moving image storage device.
[0002]
[Prior art]
2. Description of the Related Art With the rapid development of moving image processing technology, handling moving images as digital data has been widely performed. In recent years, it has become common to distribute and store moving images as encoded data of an encoding method such as MPEG-1, 2, 4, or the like.
[0003]
In addition to decoding the encoded data with a video device or a computer to view the moving image, the mobile terminal (for example, a mobile phone or a PDA (Personal Data Appliance)) decodes the encoded data to decode the moving image. Services to watch are also being put to practical use.
[0004]
In this service, encoded data of a moving image distributed from a broadcasting station or a communication station is stored in a moving image storage server installed in a home or the like. Then, the user can view the moving image at a desired place by obtaining the encoded data from the moving image storage server using the portable terminal.
[0005]
The problem with viewing moving images on a portable terminal is the narrow communication band. In order to solve this, a method of reducing the bit rate of encoded data has been proposed (for example, Patent Document 1).
[0006]
However, when the bit rate is reduced, the quality of a moving image deteriorates significantly. Therefore, it is desirable to convert to a coding method having good image quality even at a low bit rate. Patent Literature 2 proposes a technique for converting a moving image encoding method.
[0007]
By means of such techniques as bit rate reduction and coding system conversion, encoded data can be received in real time by a mobile terminal even when the communication band is narrow, and moving images can be reproduced without interruption.
[0008]
[Patent Document 1]
JP 2001-339460 A
[Patent Document 2]
JP 2002-185969 A
[Problems to be solved by the invention]
Generally, the screen of a mobile terminal is narrower and has a smaller number of pixels than a home television. On the other hand, the moving images and the encoded data of the moving images stored in the moving image storage server are often created for home televisions. Therefore, if the stored moving image is to be displayed as it is on the portable terminal, the person or character becomes small like a bean grain, making it difficult to see.
[0011]
In addition, the load on the mobile terminal is increased by an enlargement process for displaying an image coded with a small number of pixels on a full screen, and a rotation process for displaying a horizontally long image rotated 90 degrees on a screen of a vertically long mobile terminal. , The power consumption increases, and the driving time when driving with a battery is shortened.
[0012]
Therefore, an object of the present invention is to provide a moving image storage device that can transmit a moving image that is easy for a user to view while reducing the load on a mobile terminal.
[0013]
[Means for Solving the Problems]
In order to solve the above-described problems, the moving image storage device of the present invention performs transformation of a moving image together with conversion of a moving image encoding method.
[0014]
For this purpose, an input unit for inputting first encoded data of a moving image encoded by a first encoding method, a storage unit for storing the first encoded data, and a storage unit for storing the first encoded data. A decoding unit that decodes the first encoded data to generate a moving image, a deforming unit that performs a deformation process on each frame of the moving image, and a second encoding method that converts the deformed moving image to a second encoding method. And an output unit that outputs the second encoded data.
[0015]
The deformation processing includes enlargement, reduction, rotation, and clipping.
[0016]
In addition, the user may give a request regarding a deformation process such as an enlargement / reduction ratio or a cut-out range, and the deformation unit may perform the deformation according to the request.
[0017]
A moving image conversion apparatus according to the present invention includes a decoding unit that decodes encoded data of a moving image in a first encoding format, and a deformation unit that performs a deformation process on each frame of the moving image obtained by decoding. And an encoding unit that encodes the transformed moving image using the second encoding method.
[0018]
Further, in the moving picture conversion device of the present invention, the deforming unit may receive a request related to a deformation process from the outside, and perform the deformation process according to the request.
[0019]
The deformation processing includes enlargement, reduction, rotation, and clipping.
[0020]
In addition, the user may give a request regarding a deformation process such as an enlargement / reduction ratio or a cut-out range, and the deformation unit may perform the deformation according to the request.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
(Overview) FIG. 2 is a view for explaining an example of a system using a moving image storage device according to an embodiment of the present invention.
[0022]
The moving image storage device 202 receives and stores moving image data distributed by broadcasting or communication from the content provider 201. Then, the stored moving image data is transmitted to the user's portable viewing terminal 204 via the network 203 in response to the user's request.
[0023]
The moving image storage device 202 receives and stores MPEG-2 encoded data of a moving image distributed from a broadcasting station or a communication station. Then, the data is converted into MPEG-4 encoded data and transmitted to the portable viewing terminal 204 in response to a user request.
[0024]
When converting the stored MPEG-2 encoded data to MPEG-4 encoded data, the moving image storage device 202 performs a modification so that the moving image can be easily viewed on the portable viewing terminal 204.
[0025]
For example, the moving image 301 in FIG. 3 is rotationally converted so that the longitudinal direction of the screen 321 matches the longitudinal direction of the moving image 301 as in a moving image displayed on the portable viewing terminal 311, or FIG. For example, a part of the moving image 401 of FIG. 4 is cut out and an image of the cut out part is displayed like a moving image displayed on the screen 420 of the portable viewing terminal 410.
[0026]
The moving image storage device 202 temporarily decodes the MPEG-2 encoded data, performs the above-described modification, and encodes the data in the MPEG-4 format. Then, it transmits to portable viewing terminal 204.
[0027]
The user requests the video storage device 202 via the network 203 at the mobile viewing terminal 204 to transmit the encoded data of the stored video. At this time, in addition to the identification name (for example, file name) of the moving image, a policy of a deformation process (for example, cutout / rotation) for making the moving image easier to see, an encoding method and a bit for transmitting to the portable viewing terminal 204 Communicate rate requirements.
[0028]
Then, the portable viewing terminal 204 receives the encoded data transmitted from the moving image storage device 202 in response to a user request. By simply decoding the encoded data with the portable viewing terminal 204, it becomes possible to view a moving image that has become easier to view. Therefore, the load on the portable viewing terminal 204 can be reduced.
[0029]
The network 203 may be wired or wireless. Also, the means (communication / broadcast) by which the content provider 201 distributes a moving image may be wired or wireless.
[0030]
Here, an example is described in which the moving image storage device 202 receives and stores the MPEG-2 encoded data, converts the data into MPEG-4 encoded data, and transmits the data to the portable viewing terminal 204. Is not limited to this combination. It may be configured to use MPEG-1 or another moving picture coding method.
[0031]
(First Embodiment) Hereinafter, a moving image storage device according to a first embodiment of the present invention will be described with reference to the drawings.
[0032]
(Schematic Configuration) FIG. 1 is a diagram for explaining the configuration of a moving image storage device according to the first embodiment of the present invention.
[0033]
The moving image storage device of the present embodiment includes a moving image input unit 101 for receiving encoded data of a moving image from outside or inputting encoded data of a moving image by an arbitrary method, and a moving image received or input. The moving image storage unit 102 stores encoded image data, and a request receiving unit 107 that receives a request from a user.
[0034]
Further, the read control unit 103 reads the encoded data of the moving image requested by the user from the moving image storage unit 102, and converts the encoding method of the encoded data of the read moving image so that the user can easily view the data. A moving image converter (transcoder) 110 for performing transformation processing; and a moving image output unit 106 for transmitting the converted coded data.
[0035]
The moving image conversion unit (transcoder) 110 includes a moving image transformation unit 104 that transforms the moving image obtained by decoding the read encoded data of the moving image so that the user can easily view the moving image. A moving image encoding unit 105 that encodes the generated moving image in a format that can be viewed on a user's portable viewing terminal.
[0036]
As described above, since the moving image storage device deforms the moving image storage device in advance so that the user can easily view it and then outputs it to the portable viewing terminal, the load on the portable viewing terminal can be reduced, and the driving time can be lengthened. it can.
[0037]
(Schematic operation) The basic operation of the moving image storage device of the present embodiment is as follows.
[0038]
First, the moving image input unit 101 receives encoded data of a moving image such as a broadcast program distributed from a content provider via broadcasting (wired or wireless) or a network, and stores the encoded data in the moving image storage unit 102.
[0039]
The request receiving unit 107 receives various requests from the user's portable viewing terminal. The request is, for example, a request to transmit / stop encoded data, a request to transform a moving image, a specification of an encoding method and a bit rate, a request to transmit a list of stored moving images, and the like. Then, the request receiving unit 107 notifies the read control unit 103, the moving image transforming unit 104, and the moving image encoding unit 105 of the received request.
[0040]
The read control unit 103 reads the encoded data from the moving image storage unit 102 based on the notification from the request receiving unit 107. The read encoded data is decoded by the moving image transforming unit 104 to perform a transformation process, and is encoded by the moving image encoding unit 105. Then, the moving image is output from the moving image output unit 106 to the portable viewing terminal of the user.
[0041]
The transformation process of the moving image transformation unit 104 and the encoding process of the moving image encoding unit 105 are performed based on information notified from the request receiving unit 107. For example, the bit rate in the encoding process uses a value as requested by the user to the request receiving unit 107.
[0042]
The encoded data generated by the moving image encoding unit 105 is transmitted from the moving image output unit 106 to the portable viewing terminal of the user.
[0043]
(Moving Image Input Unit 101) The moving image input unit 101 receives encoded data of a moving image encoded by the MPEG-2 system transmitted from a broadcasting station or a communication station. Then, the received encoded data is sequentially output to the moving image storage unit 102.
[0044]
The moving image input unit 101 includes a buffer memory and minimizes loss of encoded data due to a change in a communication state, a radio wave state, or the like.
[0045]
The input encoded data may be stored in a hard disk, an optical disk, or a semiconductor memory in the form of an electronic file. In addition, streaming transmission, digital broadcasting, electronic mail, and the like may be transmitted using a network or radio waves.
[0046]
In the present embodiment, the encoded data of the moving image to be distributed is in the MPEG-2 format, but may be in another encoding format (for example, MPEG-1, MPEG-4, H264).
[0047]
In addition, not only coded data but also analog moving images may be distributed. In the case of an analog video, the video is encoded by the video input unit 101 and then output to the video storage unit 102. Note that, in this case, any encoding method can be used as in the above, but in the present embodiment, MPEG-2 is used.
[0048]
In addition, a moving image (regardless of analog data or encoded data) to be distributed may be encrypted (including scramble). In this case, decoding and restoration are performed by the moving image input unit 101.
[0049]
(Moving Image Storage Unit 102) The moving image storage unit 102 is a storage device for storing the MPEG-2 encoded data received by the moving image input unit 101.
[0050]
The storage device is, for example, a hard disk drive, an optical disk drive, or a semiconductor memory. In this embodiment, a hard disk drive is used. The MPEG-2 encoded data received by the moving image storage unit 102 is stored in a hard disk drive.
[0051]
If the MPEG-2 encoded data of the program is provided on a recording medium including an optical disk, a semiconductor memory, or a hard disk drive, the contents of the recording medium are read out by the moving image input unit 101 and the moving image Alternatively, the recording medium itself may be used as the moving image storage unit 102.
[0052]
(Read Control Unit 103) The read control unit 103 is a control device that receives a user's request via the request receiving unit 107, and reads encoded data of a moving image requested by the user from the moving image storage unit 102.
[0053]
When the user's request is the identification name of the file storing the encoded data, the file is searched for and read from the moving image storage unit 102. When a specific part of a specific file is designated, such as “from xx minute xx seconds to △△ minute △△ second of file XX”, the file is searched and the corresponding part is read.
[0054]
(Moving image deforming unit 104) The moving image deforming unit 104 includes a decoder 1041 for decoding MPEG-2, and a DSP 1042 for deforming each frame of the moving image.
[0055]
The moving image transforming unit 104 decodes the read encoded data by the decoder 1041. Then, the moving image obtained by decoding is subjected to a deformation process using the DSP 1042 in accordance with the user's request received via the request receiving unit 107. In the moving image storage device of the present embodiment, rotation and clipping are performed as deformation.
[0056]
Whether rotation or cutout is performed or both are performed, and the range of cutout when performing cutout is determined by the user's request received via the request receiving unit 107.
[0057]
FIG. 3 shows an example in which rotation is performed. When the mobile viewing terminal is a mobile phone, a PDA (Personal Data Appliance), or the like, it generally has a vertically long display in many cases.
[0058]
Therefore, if a horizontally long moving image such as a moving image 301 created for a television is to be displayed as it is, the size of the moving image is reduced as in the portable viewing terminal 310 and the moving image is displayed on the screen 320. The area where is not displayed appears. On the other hand, if the image 301 is rotated 90 degrees to the right and displayed as in the terminal 311, the display area of the screen 321 can be effectively used, and the size of the moving image can be increased.
[0059]
Therefore, the user issues a request for “deformation: 90 degrees to the right”. This request may be included in a request for transmitting a moving image or may be issued as an independent request. The request is notified to the moving image deforming unit 104 via the request receiving unit 107, and upon receiving this notification, the moving image deforming unit 104 performs a deformation of rotating the image 90 degrees to the right.
[0060]
FIG. 4 shows an example in which clipping is performed. When the mobile viewing terminal is a mobile phone, a PDA, or the like, the display is small, and it may be difficult to confirm what kind of subject is displayed on the screen 420 when viewing a moving image. Therefore, if the periphery of the subject in the moving image is cut out and distributed to the portable viewing terminal 310, the contents of the moving image can be easily grasped.
[0061]
Therefore, the user issues a cut-out request such as “deformation: cut-out (OO, OO)-(XX, XX)”. This request may be included in a request for transmitting a moving image or may be issued as an independent request. The request is notified to the moving image deforming unit 104 via the request receiving unit 107, and upon receiving this notification, the moving image deforming unit 104 has (OO, OO) and (XX, XX) diagonally. Cut out a rectangular area.
[0062]
Note that the cutout request is not limited to this, and may be, for example, a designation method such as “△△ pixel × □□ pixel centering on (，, ○)”.
[0063]
Note that the decoder 1041 may be configured as dedicated hardware (semiconductor integrated circuit) or may be realized as software. Regarding the DSP 1042, the processing may be performed using a general-purpose CPU.
[0064]
(Moving Image Encoding Unit 105) The moving image encoding unit 105 encodes the transformed moving image by the MPEG-4 system. In general, it is expected that encoded data of a moving image stored in the moving image storage unit 102 is high-quality data having a very high bit rate (for example, 1000 kbps or more).
[0065]
In the case of a portable viewing terminal, not only is it difficult to receive such high bit rate data, but also it is difficult to decode such high bit rate data due to processing capacity and battery issues. it is conceivable that. Actually, it will be necessary to suppress the bit rate to 100 to 200 kbps or less.
[0066]
In encoding, the moving image encoding unit 105 determines a bit rate according to a user request received via the request receiving unit 107.
[0067]
In the present embodiment, the moving picture coding unit 105 performs coding by the MPEG-4 method, but performs coding by another coding method (for example, MPEG-1, MPEG-2, H264). You may comprise so that it may be. It should be noted that a configuration may be adopted in which a plurality of encoding methods can be handled, so that the user can select an encoding method.
[0068]
When a plurality of encoding schemes are supported, it is considered easy to implement if the moving picture encoding unit 105 is configured to include a memory and a CPU, and the encoding function is realized by software.
[0069]
(Moving Image Output Unit 106) The moving image output unit 106 outputs the encoded data generated by the moving image encoding unit 105 to the portable viewing terminal.
[0070]
(Request receiving unit 107) The request receiving unit 107 communicates with the user's portable viewing terminal, and receives various requests from the user. As described above, the request includes, for example, a request for transmitting encoded data, a request for transforming a moving image, and a designation of an encoding method and a bit rate.
[0071]
The request received by the request receiving unit is, for example, “request: transmission, file name: xxx, deformation: rotation (right 90 degrees), encoding method: MPEG-4, bit rate: 200 kbps”, “request: stop”, “ Deformation: reduction (○ ×× pixel), “deformation: cutout ((（,）) − (xx, xx))” and the like can be considered.
[0072]
The request receiving unit 107 analyzes whether the received request is to be notified to the read control unit 103, the moving image transforming unit 104, or the moving image encoding unit 105, and notifies the appropriate destination of the request.
[0073]
For example, a request for transmitting encoded data is considered to include a request for designating data (file identification name and range) to be read, a request for a modification method, and a request for designating a bit rate for transmission. Can be
[0074]
The request receiving unit 107 analyzes the transmission request, specifies a request for designating data to be read to the read control unit 103, a request for a modification method to the moving image transformation unit 104, and designates a bit rate and an encoding method. The request is notified to the video encoding unit 105.
[0075]
In the above example, if "request: transmission, file name: xxx, deformation: rotation (right 90 degrees), encoding method: MPEG-4, bit rate: 200 kbps", the read control unit 103 "File name: XXX", "deformation: rotation (right 90 degrees)" in the moving image transformation unit 104, "encoding method: MPEG-4" and "bit rate" in the moving image encoding unit 105. : 200 kbps ".
[0076]
Also, for example, when clipping is performed by the moving image transforming unit 104, a request to change the clipping range from the portable viewing terminal is expected. When such a request is received, the moving image transforming unit 104 is notified.
[0077]
(Modification 1) In the present embodiment, what kind of modification processing is performed depends on the user's request. However, if the performance of the portable viewing terminal is fixed (for example, a specific model), Alternatively, the processing content may be fixed at a preset value.
[0078]
If a plurality of types of mobile viewing terminals are used, information on the capability of the user's mobile viewing terminal may be received and automatically determined from the information.
[0079]
For example, the size of the clipping range in clipping and the enlargement / reduction ratio of the screen may be automatically determined by receiving information on the size of the screen of the portable viewing terminal. Alternatively, whether to rotate the image may be automatically determined based on the number of pixels in the vertical and horizontal directions of the screen.
[0080]
Further, not only the modification but also the encoding method and the bit rate may be determined based on information on the communication speed detected by the moving image storage device or received from the portable viewing terminal.
[0081]
When automatically determined, the request may be determined by the request receiving unit 107 or may be determined by each unit such as the moving image transforming unit 104 and the moving image encoding unit 105.
[0082]
(Modification 2) In this embodiment, only rotation / cutout is dealt with, but other modifications may be made. For example, reversing left and right is very useful in places such as a barber shop or a beauty shop where the light is reflected on a mirror for viewing.
[0083]
The reduction is useful for grasping the entire image on a screen having a small number of pixels such as a portable viewing terminal. In addition, when cutting out is not sufficient, enlargement may be performed together.
[0084]
In addition, deformation may be performed in accordance with an assumed viewing environment such as upside down, parallel movement of position, and curvature.
[0085]
(Modification 3) In the present embodiment, for example, when metadata related to a moving image typified by MPEG-7 metadata is also distributed, the range of enlargement or clipping can be specified by relying on the metadata. good.
[0086]
For example, in the case of a soccer match, the user performs a specification such as “cut out 100 pixels × 100 pixels centering on the ball”, and the moving image transformation unit 104 refers to the metadata to “ball” in the moving image. Is searched for, and a process of cutting out “100 pixels × 100 pixels” around the position is performed.
[0087]
Further, when performing the cutout processing and the enlargement processing, in addition to displaying the cutout / enlarged portion 501 as shown in FIG. It is good because you can grasp whether the position is cut out.
[0088]
(Effects of this Embodiment) As described above, according to the present embodiment, when the moving image encoding device converts the coding method of a moving image, the moving image is subjected to a deformation process so that the moving image can be easily viewed on the portable viewing terminal of the user. Therefore, it is possible to transmit a moving image that is easy for the user to view while reducing the load on the portable viewing terminal.
[0089]
In addition, in the case of performing cutout or reduction as a deformation process, data obtained by truncating some information of an image is transmitted to a portable viewing terminal, so that a moving image can be viewed comfortably without interruption even in an environment where a communication band is narrower than before. be able to.
[0090]
【The invention's effect】
As described above, according to the present invention, since the moving image is transformed in the moving image storage device, it is possible to transmit a moving image that is easy for the user to view while reducing the load on the user's portable viewing terminal. .
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a first moving image storage device of the present invention.
FIG. 2 is an image diagram illustrating a system operation using the moving image storage device according to the embodiment of the present invention.
FIG. 3 is a diagram illustrating a modified example of a moving image. FIG. 4 is a diagram illustrating a modified example of a moving image. FIG. 5 is a diagram illustrating a modified example of a moving image.
101 moving image input unit 102 moving image storage unit 103 read control unit 104 moving image transformation unit 105 moving image encoding unit 106 moving image output unit 107 request receiving unit 110 moving image conversion unit 1041 decoder 1042 DSP
201 content provider 202 moving image storage device 203 network 204 portable viewing terminal

Claims (14)

A moving image storage device that stores moving image data and provides the moving image data to a portable viewing terminal of a user,
A storage unit for storing first encoded data of the first encoding method;
A decoding unit that decodes the first encoded data stored in the storage unit to generate a moving image;
A deformation unit that performs a deformation process on each frame of the moving image,
An encoding unit that encodes the transformed moving image to generate second encoded data of a second encoding scheme;
An output unit that outputs the second encoded data;
Video storage device equipped with The moving image storage device according to claim 1, wherein the deforming unit performs a deformation process including enlarging, reducing, cutting out, and rotating each frame of the moving image. The moving image storage device according to claim 1, wherein:
Furthermore, a request receiving unit for receiving a request from the user is provided,
The moving image storage device according to claim 1, wherein the deformation unit performs a deformation process according to a request of the user. 4. The moving image storage device according to claim 3, wherein the request receiving unit receives a request from a user to specify a clipping range as needed, and the deforming unit performs a clipping process according to the request. The request receiving unit receives a request including information on the number of pixels of the screen of the mobile viewing terminal,
4. The moving image storage device according to claim 3, wherein the deformation unit determines an enlargement / reduction rate in enlargement / reduction processing or a width of a cutout range in the cutout processing from the information. The encoding unit, a CPU, a memory storing a program that causes the CPU to perform encoding processing by a plurality of methods,
5. The moving image storage device according to claim 1, further comprising: selecting a coding method according to a user request received via the request receiving unit, and performing coding. 2. The moving image storage device according to claim 1, wherein the moving image input unit receives a moving image and performs encoding by a first encoding method. 2. The moving image storage device according to claim 1, wherein the moving image input unit receives the encrypted first encoded data and decrypts the first encoded data. A moving image storage device that stores moving image data and provides the moving image data to a portable viewing terminal of a user via a network,
A moving image input unit that inputs first encoded data of a first encoding method including metadata, a storage unit that stores the first encoded data,
A decoding unit that decodes the first encoded data stored in the storage unit to generate a moving image, a request receiving unit that receives a request from a user,
A deforming unit that cuts out an image from each frame of the moving image,
An encoding unit that encodes the transformed moving image to generate second encoded data of a second encoding scheme;
An output unit that outputs the second encoded data;
With
The request receiving unit receives a deformation request including a keyword for performing a search for the metadata and size information of an image to be cut out,
The moving image storage device, wherein the deforming unit performs a search of the metadata based on the keyword, determines a cutout range together with the result and the size information, and cuts out an image. . A decoding unit for decoding encoded data of the first encoding format of the moving image;
A deformation unit that performs a deformation process on each frame of a moving image obtained by decoding,
An encoding unit that encodes the transformed moving image using a second encoding method;
A moving image conversion device comprising: The moving image conversion apparatus according to claim 10, wherein the deforming unit performs a deformation process including enlarging, reducing, cutting out, and rotating each frame of the moving image. 11. The moving image conversion apparatus according to claim 10, wherein the deformation unit receives a request related to a deformation process from the outside, and performs the deformation process according to the request. The moving image conversion device according to claim 11, wherein the deforming unit receives a request from a user to specify a cutout range as needed, and performs a cutout process in accordance with the request. The deforming unit receives a request including information on the number of pixels of the screen of the portable viewing terminal, and determines an enlargement / reduction ratio in the enlargement / reduction processing or a width of the extraction range in the extraction processing from the information. The moving image conversion device according to claim 3.

Images