Missing I-frames on DM6467 DVEVM h.264 BP encoder

Have you tried analyzing the bitstream using a syntax analyzer such as Elecard StreamEye? The first frame encoded will be IDR frame. Depending on Intra Frame Interval, subsequent frames are coded as I. Rest of the frames are coded as P. I think the hex sequence 00 00 00 01 65 you see at the beginning of the bitstream corresponds to IDR.

Thank you.

I used the Elecard StreamEye and found out that indeed there are I-frames every 30 fames as it should, so I was wrong, since I thought that IDR is the same as I-frame.

I know that many encoders (like ffmpeg for example) use IDR and not I-frames every some frames and this is done for allowing streaming to work although packets are lost. An IDR includes all the required information for synchronizing back after packet loss when doing streaming.

Also, the TI h.264 BP decoder requires an IDR to start decoding and if I give it I-frame at the beginning it will not decode.

This is still a problem to me. Is there a possibility to output IDR frames every 'IntraFrameInterval' from the TI H.264 BP encoder and not I-frame?

I agree with you that the Streaming Media applications (and in general, applications that involve networking) would want to have an IDR frame every T seconds to recover from possible packet loss conditions. However, this is not a generic requirement across all application domains.

The same effect of having periodic IDR frames can be achieved at application level through the following:

1. IntraFrameInterval = 0

This will ensure that the encoder codes the very first frame as IDR and rest of the frames as Inter.

2. For every N frames, make a control call with "forceFrame" parameter set to IVIDEO_IDR_FRAME. This will force the immediate next frame to be coded as IDR

#define IDR_INTERVAL  30

IVIDENC1_DynamicParams dynParams;

IVIDENC1_Status status;

int nFrames=1;

...

while ( !stop )

{

   if (0 == nFrames % IDR_INTERVAL)

   {

     dynParams.forceFrame = IVIDEO_IDR_FRAME;

     VIDENC1_control(handle, XDM_SETPARAMS, &dynParams, &status);

  }

  ...

  VIDENC1_process(handle, &inBufDesc, &outBufDesc, &inArgs, &outArgs);

  nFrames++;

  ...

}

I tried your suggestion for forcing IDR frames every 30 frames but I keep getting only 1 IDR at start of encoded file and no more IDRs later.

Any other suggestion?

Nir,

You called the Control function using XDM_SETPARAMS every 30 frames? In the output that you get are you getting an I frame instead of an IDR?

Meanwhile I got over this problem. I now get IDR frames. It seems I send a wrong struct size.