4 Replies Latest reply on Dec 14, 2011 8:45 PM by oxydius

    Open Video Decode problems

    diskerr


      I'm currently working with video codecs and very interested in OVD.
      My system is: i5-750 / HD6870 / Win7 x64 / VS2010 / AMD APP SDK 2.5 / Catalyst 11.7 & 11.11.

      I have encounted some problems using your OVD and the OVDecodeRender sample.


      1. When I remove a busy-waiting - while(timeMS < 33) - in renderOneFrame() function to test the maximum capability of OVD, it sometimes produces corrupted raw frames.
      Perhaps the decoding process is not finished even with clWaitForEvents() calls so it requires additional delays. Is this a bug or my misunderstanding?

      2. Slightly increasing decoding latency. I modified the sample to play the stream repeatedly.
      In the beginning of the decoding, the latency between OVDecodePicture() and clWaitForEvnets() is about 0.4 ms,
      but it gets longer and longer until it reaches about 3ms and then goes to 0.4ms and gets longer again.
      Although the decoding latency can vary, increasing latency and reset doesn't make sense. Is there a problem?

      3. OVDecodeCreateSession() consumes so much time (about 2-3secs) and I think this can be a major problem for many applications.
      One strange thing is, when I run the sample with profiling session (alt+f2) in VS2010, OVDecodeCreateSession() takes only 300ms and everything works fine.
      Do you have any idea for this problem?

      4. The OVDecodeRender works fine with catalyst 11.7 but crashes in OVDecodeGetDeviceCap() function with 11.11. No way to make this work?

        • Open Video Decode problems
          diskerr

          please provide some information for me...

          or this is a user-error? :-(

            • Open Video Decode problems
              himanshu.gautam

              Thanks for reporting these issues.

              It would be helpful if you can send whatever changes you had don to the sample, in order to reproduce the issues.

                • Open Video Decode problems
                  diskerr

                  I downloaded your sample from here: http://developer.amd.com/downloads/OVDecodeRender.zip

                  1. remove busy waiting

                  file GLRenderFrame.cpp, function renderOneFrame(), line 152

                  while(false && timeMS < 33) // while(timeMS < 33)

                  2. play the sample stream repeatedly

                  file OVDecodeRender.cpp, function OVDecodeRender::decodeParserRender(), line 2102, added

                  if (iFramesDecoded == 1000) iFramesDecoded = 0;

                  3.

                  no code changes at all, I just add QueryPerformanceCounter() to measure time.

                   

                  4.

                  always reproduced without ""any"" code changes.

                   

                  as you can see, the sample itself or just a single line modification can reproduce these problems...

                  Thanks for your reply.

                    • Open Video Decode problems
                      oxydius

                      I also had similar problems with OpenVideo in previous driver/SDK versions, so I tested the OVD sample code as-is with latest SDK 2.6 and Catalyst 11.12 on different 64-bit Win7 systems :

                      890GX platform with Phenom II X6 and one Radeon 6450 : hard reset

                      790FX platform with Phenom II X4 and two Radeon 6950 : blue screen

                      Is there a newer version of the OVD sample code that doesn't cause system crashes?