MPEG coded picture decoding apparatus

• US 6,141,385 A
• Filed: 03/27/1997
• Issued: 10/31/2000
• Est. Priority Date: 03/28/1996
• Status: Expired due to Term

• Current Assignee: Acer, Inc.
• Original Assignee: NEC Corporation
• Inventors: Yamaji, Hirotaka
• Primary Examiner(s): LEE, RICHARD J
• Application Number:
  US08/827,474
• Time in Patent Office: 1,314 Days
• Field of Search: 348/384, 348/390, 348/400-402, 348/405-407, 348/409-413, 348/415, 348/416, 348/420, 348/426, 348/607, 348/699, 348/714-716, 348/718, 348/845 , 348/845.1, 382/232, 382/236, 382/238
• US Class Current: 375/240.27
• CPC Class Codes: H04N 19/00 Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 19/70 characterised by syntax aspects related to video coding, e.g. related to compression standards
• CPC Class Codes: H04N 19/89 involving methods or arrangements for detection of transmission errors at the decoder
• CPC Class Codes: H04N 21/43072 of multiple content streams on the same device
• CPC Class Codes: H04N 21/44004 involving video buffer management, e.g. video decoder buffer or video display buffer
• CPC Class Codes: H04N 21/6375 for requesting retransmission , e.g. of data packets lost or corrupted during transmission from serverARQ protocols H04L1/18; implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP] H04L69/16

Abstract

An MPEG coded picture decoding apparatus is provided which can display video data quite the same as original data even if a miss of MPEG coded video data occurs in a transmission line or the like. The MPEG coded picture decoding apparatus includes a stream buffer memory for storing an MPEG stream, a pack header processing section for separating a pack header of the MPEG stream and extracting SCR information, a PES packet processing section for separating a header of a PES stream, extracting PTS information and separating packets, a GOP detection section for detecting a GOP of a video stream, a video buffer memory for storing the video stream, a video MPEG decoding section for MPEG decoding the video stream, a decoded data storage section for storing and managing one picture frame, a video display processing section for storing several picture frames and reading out at a display timing, and an error information processing section for supervising a picture frame memory at each display timing and developing a video re-sending request when the picture frame memory is in an irregular condition.

Claims

1. A coded picture decoding apparatus for processing coded video data transmitted thereto from a coding multiplexing side and decoded by a decoding element, said decoding apparatus comprising:

a memory for temporarily storing the decoded video data in units of one picture frame;

a memory management section for supervising said memory to detect whether or not picture data for the stored frames are stored into said memory completely without a miss;

a video display processing section including a display memory into which video data for a plurality of picture frames successively read out from said memory are temporarily stored and from which the video data are read out in units of one picture frame so as to be displayed in the same order as the video data were stored;

an error processing section for checking memory storage information at an output of said memory management section at each video display timing and for outputting, when the memory storage information is not outputted from said memory management section, error information determining that a miss of data has occurred with a picture frame stored immediately before the display timing, and delivering a re-sending request to said coding multiplexing side to re-send video data for the one picture frame in which the miss of data has occurred while maintaining any subsequently received error-free picture frames in said video display processing section display memory; and

a control section for storing video data of the one picture frame re-sent from said coding multiplexing side into said display memory of said video display processing section before the re-sent video data are displayed.

2. The coded picture decoding apparatus according to claim 1, wherein said re-sending request is for a GOP which includes the picture frame in which the miss of data has occurred and wherein said control section stores the GOP.

3. A coded picture decoding apparatus, comprising:

a first memory for successively and temporarily storing a multiplexed stream inputted thereto from a coding multiplexing side via a transmission line and a line input interface and multiplexed from coded bit streams of a plurality of media including video and audio data;

a pack header processing section for separating a pack header of the multiplexed stream read out from said first memory in response to a first control signal and extracting system clock reference information for a system clock reference;

a packet processing section for separating a packet header from the multiplexed stream from said pack header processing section from which the pack header has been separated, extracting presentation time stamp information for a time reference and separating the multiplexed stream from said pack header processing section in units of a packet of each of the plurality of media;

a GOP detection section for detecting a GOP from a video stream of video packets separated by said packet processing section;

a first control section for outputting the first control signal and a second control signal in response to a GOP detection signal from said GOP detection section;

a second memory for temporarily storing the video stream of the video packets separated by said packet processing section and being controlled by the second control signal from said first control section to read out the video stream temporarily stored therein in units of a GOP;

a video decoding section being controlled by a third control signal to decode video data in units of one picture frame outputted from said second memory;

a third memory for temporarily storing decoded video data for one picture frame from said video decoding section;

a memory management section for supervising a storage condition of the decoded video data for one picture frame into a storage region of said third memory and controlling, when the storage condition is regular, said third memory to output the decoded video data for one picture frame stored in said third memory, but outputting, when the storage condition is irregular, first error information;

a fourth memory for temporarily storing the decoded video data for one picture frame outputted from said third memory for a first number of picture frames;

a video display control section for controlling the decoded video data read out in units of one picture frame from said fourth memory in response to a fourth control signal so that the decoded video data is outputted at a video display timing;

a digital to analog conversion section for performing digital to analog conversion of the decoded video data for each one picture frame from said video display control section and outputting and supplying the resulting analog decoded video data as a decoded picture signal to an external video viewer;

a second control section for outputting the third and fourth control signals in response to a fifth control signal so that the third control signal is supplied to said second memory and the fourth control signal is supplied to said fourth memory;

a display timing production section for producing and supplying the video display timing to said video display control section in order to allow the decoded picture signal outputted from said digital to analog conversion section to be displayed at a timing on a picture monitor of the video viewer;

an error information processing section for supervising an input thereto of the first error information outputted from said memory management section at a timing of a period equal to that of the video display timing outputted from said display timing production section and outputting, when the first error information is inputted thereto, a video re-sending request signal based on the error information to said coding multiplexing side to request for re-sending of video data of the same picture frame as that of the video data with regard to which the first error information is outputted;

a clock generation section for generating a decoding side clock signal to be used for decoding based on the system clock reference information extracted by said pack header processing section;

a time information production section for producing decoding side time information to be used for decoding based on the presentation time stamp information extracted by said packet processing section;

a synchronization timing production section for producing an AV synchronization timing for synchronization between the video and audio data upon decoding based on the decoding side time information outputted from said time information production section; and

a CPU control section for receiving the decoding side clock signal from said clock generation section, the decoding side time information from said time information production section, the GOP detection signal from said GOP detection section and the video re-sending request signal from said error information processing section to drive a host CPU to control the decoding processing of said decoding section via a CPU bus and to output the fifth control signal to control said second control section and sending out the video re-sending request signal to said coding multiplexing side via a line output interface and said transmission line.