DM3730 DSP mpeg2 decoder mpeg2_dec_prod.l64P issue

I dowloaded ti-dvsdk_dm3730-evm_4_02_00_06 and tested mpeg2 decoder on beagleboard xM rev. C with 640x360 mpeg1 stream. I found the following issues.

1.  Vdec2_create(Engine_Handle hEngine, Char *codecName, VIDDEC2_Params *params, VIDDEC2_DynamicParams *dynParams) failed if maxWidth and maxHeight are set to 640 and 360 respetively in *params. It is O.K. if set to 1280x720 or 720X480. In terms of its user guide, it should work from 128x96 to 1280x720

2. It doesn't work with 640x360 mpeg1. Following the first issue, maxWidth and maxHeight are set to 1280X720, Vdec2_create works. But decoder output is green strip at the bottom of screen. I tested it with ffmpeg, it works. Then I tested davinci 720x480 mpeg2 test stream, it works. Its user data document says it supports mpeg1 as well.

Thanks.

16 Replies

  • Hi Kaijun,

    Can you please share the version number of codec used?

    Thanks,

    Roopesh

  • In reply to Roopesh Rajashekharaiah Nataraja:

    Hi Roopesh,

    The Release notes say the version number is 01.00.00.01.

    For the first issue, it seems the frame width/hight must be a multiple of 16.

  • In reply to Roopesh Rajashekharaiah Nataraja:

    I also tested mpeg4 and h264 decoders with big bunk bunny mpeg4 and h264 720p streams. Sometimes video could be paused a while on a complicated motion background, e.g. in case of zooming. It seems DSP has no enough speed to handle decoding. mpeg4 and h264 codec versions are 5.0.3.0 and 1.0.3.0 respectively.

  • Hi Kaijung Tang,

     Can you please share the 640x360 stream which shows the green strip ?
     
     I guess the displayBufs.frameHeight in outArgs is not populated correctly by decoder.
     It may have rounded this to next multiple of 16 (368) which probably explains the green strip.
     It is is also possible that it is mpeg1 specific issue in mpeg2 decoder.
     
     However I can confirm the exact issue once you upload the stream.

    Thanks and Regards,
    Jay

  • In reply to Jay Shingala:

    Click here to play this video

    Please see attached file.

  • In reply to Jay Shingala:

    Hi Jay,

    Have you resolved the issue? If yes, please give me a new release for test.

    Kai

  • In reply to Kaijun Tang:

    Hi Kai,

    Apologies for late response to this issue.

    We have made the following observations with the clip you uploaded:
     1. 640x360 stream that you uploaded is in mpg file format and it embeds raw mpeg2 stream and not mpeg1 stream as reported earlier.
     2. After extracting the raw mpeg2 stream and testing with decoder, it was observed that  display height was indicated as 368 which explains small green strip at bottom as predicted earlier
     
    We have made a fix in the decoder to give out actual width and height for non multiple of 16 resolutions.
    We have also fixed the decoder instance creation failure for resolutions non-multiple of 16.

    Can you confirm if you only saw small green strip (about 8 lines) at bottom of the screen.
    I am asking this question because when the test team here tested with mpg container file on gstreamer, huge black and green strip is seen as an output which could be an issue in mpg parser.
    But when I play the raw stream (extracted offline from the mpg file), I am seeing proper video.

    Regards,
    Jay

     

  • In reply to Jay Shingala:

    Hi Jay,

    For this test stream, I saw black screen plus a green strip at the bottom. But for other mpeg1/2 streams with non-multiple of 16 height, I saw a green strip at the bottom.

  • In reply to Kaijun Tang:

    4744.2021.test.zip

    We have fixed the small green strip issue at the bottom (small because it is only 8 lines when image height is 360).
    However the black + green strip for the specific mpg stream you uploaded looks like a bug in mpg parser and not the mpeg2 decoder.
    I say this because the raw mpeg2 stream (extracted from mpg) plays fine.
    I have attaced the raw m2v stream in case you want to test it out.

    Regards,
    Jay

  • In reply to Jay Shingala:

    Hi Jay,

    This test stream is still black+green strip.