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Bug de détection d’ogg
22 mars 2013, par
Mis à jour : Avril 2013
Langue : français
Type : Video
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flv created using ffmpeg library plays too fast
25 avril 2015, par Muhammad AliI am muxing an h264 annex-b stream and an ADTS AAC stream coming from IP Camera into an FLV. I have gone through all the necessary things (that I knew of) e-g stripping ADTS header from AAC and converting H264 annex-b to AVC.
I am able to create the flv file which plays but it plays fast. The params of my output format video codec are :-
Time base = 1/60000 <-- I don't know why
Bitrate = 591949 (591Kbps)
GOP Size = 12
FPS = 30 Fps (that's the rate encoder sends me data at)Params for output format audio codec are :-
Timebase = 1/44100
Bitrate = 45382 (45Kbps)
Sample rate = 48000I am using NO_PTS for both audio and video.
The resultant video has double the bit rate (2x(audio bitrate + vid bitrate)) and half the duration.
If i play the resultant video in ffplay the video playsback fast so it ends quickly but audio plays on its original time. So even after the video has ended quickly the audio still plays till its full duration.If I set pts and dts equal to an increasing index (separate indices for audio and video) the video plays Super fast, bit rate shoots to an insane value and video duration gets very short but audio plays fine and on time.
EDIT :
Duration: 00:00:09.96, start: 0.000000, bitrate: 1230 kb/s
Stream #0:0: Video: h264 (Main), yuvj420p(pc, bt709), 1280x720 [SAR 1:1 DAR 16:9], 591 kb/s, 30.33 fps, 59.94 tbr, 1k tbn, 59.94 tbc
Stream #0:1: Audio: aac, 48000 Hz, mono, fltp, 45 kb/sWhy is tbr 59.94 ? how was that calculated ? maybe that is the problem ?
Code for muxing :
if(packet.header.dataType == TRANSFER_PACKET_TYPE_H264)
{
if((packet.data[0] == 0x00) && (packet.data[1] == 0x00) && (packet.data[2]==0x00) && (packet.data[3]==0x01))
{
unsigned char tempCurrFrameLength[4];
unsigned int nal_unit_length;
unsigned char nal_unit_type;
unsigned int cursor = 0;
int size = packet.header.dataLen;
do {
av_init_packet(&pkt);
int currFrameLength = 0;
if((packet.header.frameType == TRANSFER_FRAME_IDR_VIDEO) || (packet.header.frameType == TRANSFER_FRAME_I_VIDEO))
{
//pkt.flags |= AV_PKT_FLAG_KEY;
}
pkt.stream_index = packet.header.streamId;//0;//ost->st->index; //stream index 0 for vid : 1 for aud
outStreamIndex = outputVideoStreamIndex;
/*vDuration += (packet.header.dataPTS - lastvPts);
lastvPts = packet.header.dataPTS;
pkt.pts = pkt.dts= packet.header.dataPTS;*/
pkt.pts = pkt.dts = AV_NOPTS_VALUE;
if(framebuff != NULL)
{
//printf("Framebuff has mem alloc : freeing 1\n\n");
free(framebuff);
framebuff = NULL;
//printf("free successfully \n\n");
}
nal_unit_length = GetOneNalUnit(&nal_unit_type, packet.data + cursor/*pData+cursor*/, size-cursor);
if(nal_unit_length > 0 && nal_unit_type > 0)
{
}
else
{
printf("Fatal error : nal unit lenth wrong \n\n");
exit(0);
}
write_header_done = 1;
//#define _USE_SPS_PPS //comment this line to write everything on to the stream. SPS+PPSframeframe
#ifdef _USE_SPS_PPS
if (nal_unit_type == 0x07 /*NAL_SPS*/)
{ // write sps
printf("Got SPS \n");
if (_sps == NULL)
{
_sps_size = nal_unit_length -4;
_sps = new U8[_sps_size];
memcpy(_sps, packet.data+cursor+4, _sps_size); //exclude start code 0x00000001
}
}
else if (nal_unit_type == 0x08/*NAL_PPS*/)
{ // write pps
printf("Got PPS \n");
if (_pps == NULL)
{
_pps_size = nal_unit_length -4;
_pps = new U8[_pps_size];
memcpy(_pps, packet.data+cursor+4, _pps_size); //exclude start code 0x00000001
//out_stream->codec->extradata
//ofmt_ctx->streams[outputVideoStreamIndex]->codec->extradata
free(ofmt_ctx->streams[outputVideoStreamIndex]->codec->extradata);
ofmt_ctx->streams[outputVideoStreamIndex]->codec->extradata = (uint8_t*)av_mallocz(_sps_size + _pps_size);
memcpy(ofmt_ctx->streams[outputVideoStreamIndex]->codec->extradata,_sps,_sps_size);
memcpy(ofmt_ctx->streams[outputVideoStreamIndex]->codec->extradata + _sps_size,_pps,_pps_size);
ret = avformat_write_header(ofmt_ctx, NULL);
if (ret < 0) {
//fprintf(stderr, "Error occurred when opening output file\n");
printf("Error occured when opening output \n");
exit(0);
}
write_header_done = 1;
printf("Done writing header \n");
}
}
//else
#endif /*end _USE_SPS_PPS */
{ //IDR Frame
videoPts++;
if( (nal_unit_type == 0x06) || (nal_unit_type == 0x09) || (nal_unit_type == 0x07) || (nal_unit_type == 0x08))
{
av_free_packet(&pkt);
cursor += nal_unit_length;
continue;
}
if( (nal_unit_type == 0x05) || (nal_unit_type == 0x05))
{
//videoPts++;
}
if ((nal_unit_type != 0x07) && (nal_unit_type != 0x08))
{
vDuration += (packet.header.dataPTS - lastvPts);
lastvPts = packet.header.dataPTS;
//pkt.pts = pkt.dts= packet.header.dataPTS;
pkt.pts = pkt.dts= AV_NOPTS_VALUE;//videoPts;
}
else
{
//probably sps pps ... no need to transmit. free the packet
//av_free_packet(&pkt);
pkt.pts = pkt.dts = AV_NOPTS_VALUE;
}
currFrameLength = nal_unit_length - 4;//packet.header.dataLen -4;
tempCurrFrameLength[3] = currFrameLength;
tempCurrFrameLength[2] = currFrameLength>>8;
tempCurrFrameLength[1] = currFrameLength>>16;
tempCurrFrameLength[0] = currFrameLength>>24;
if(nal_unit_type == 0x05)
{
pkt.flags |= AV_PKT_FLAG_KEY;
}
framebuff = (unsigned char *)malloc(sizeof(unsigned char)* /*packet.header.dataLen*/nal_unit_length );
if(framebuff == NULL)
{
printf("Failed to allocate memory for frame \n\n ");
exit(0);
}
memcpy(framebuff, tempCurrFrameLength,0x04);
//memcpy(&framebuff[4], &packet.data[4] , currFrameLength);
//put_buffer(pData + cursor + 4, nal_unit_length - 4);// save ES data
memcpy(framebuff+4,packet.data + cursor + 4, currFrameLength );
pkt.data = framebuff;
pkt.size = nal_unit_length;//packet.header.dataLen ;
//printf("\nPrinting Frame| Size: %d | NALU Lenght: %d | NALU: %02x \n",pkt.size,nal_unit_length ,nal_unit_type);
/* GET READY TO TRANSMIT THE packet */
//pkt.duration = vDuration;
in_stream = ifmt_ctx->streams[pkt.stream_index];
out_stream = ofmt_ctx->streams[outStreamIndex];
cn = out_stream->codec;
//av_packet_rescale_ts(&pkt, cn->time_base, out_stream->time_base);
//pkt.pts = av_rescale_q_rnd(pkt.pts, in_stream->time_base, out_stream->time_base, AV_ROUND_NEAR_INF|AV_ROUND_PASS_MINMAX);
//pkt.dts = av_rescale_q_rnd(pkt.dts, in_stream->time_base, out_stream->time_base, AV_ROUND_NEAR_INF|AV_ROUND_PASS_MINMAX);
//pkt.duration = av_rescale_q(pkt.duration, in_stream->time_base, out_stream->time_base);
pkt.pos = -1;
pkt.stream_index = outStreamIndex;
if (!write_header_done)
{
}
else
{
//doxygen suggests i use av_write_frame if i am taking care of interleaving
ret = av_interleaved_write_frame(ofmt_ctx, &pkt);
//ret = av_write_frame(ofmt_ctx, &pkt);
if (ret < 0)
{
fprintf(stderr, "Error muxing Video packet\n");
continue;
}
}
/*for(int ii = 0; ii < pkt.size ; ii++)
printf("%02x ",framebuff[ii]);*/
av_free_packet(&pkt);
if(framebuff != NULL)
{
//printf("Framebuff has mem alloc : freeing 2\n\n");
free(framebuff);
framebuff = NULL;
//printf("Freeing successfully \n\n");
}
/* TRANSMIT DONE */
}
cursor += nal_unit_length;
}while(cursor < size);
}
else
{
printf("This is not annex B bitstream \n\n");
for(int ii = 0; ii < packet.header.dataLen ; ii++)
printf("%02x ",packet.data[ii]);
printf("\n\n");
exit(0);
}
//video frame has been parsed completely.
continue;
}
else if(packet.header.dataType == TRANSFER_PACKET_TYPE_AAC)
{
av_init_packet(&pkt);
pkt.flags = 1;
pkt.pts = audioPts*1024;
pkt.dts = audioPts*1024;
//pkt.duration = 1024;
pkt.stream_index = packet.header.streamId + 1;//1;//ost->st->index; //stream index 0 for vid : 1 for aud
outStreamIndex = outputAudioStreamIndex;
//aDuration += (packet.header.dataPTS - lastaPts);
//lastaPts = packet.header.dataPTS;
//NOTE: audio sync requires this value
pkt.pts = pkt.dts= AV_NOPTS_VALUE ;
//pkt.pts = pkt.dts=audioPts++;
pkt.data = (uint8_t *)packet.data;//raw_data;
pkt.size = packet.header.dataLen;
}
//packet.header.streamId
//now assigning pkt.data in repsective if statements above
//pkt.data = (uint8_t *)packet.data;//raw_data;
//pkt.size = packet.header.dataLen;
//pkt.duration = 24000; //24000 assumed basd on observation
//duration calculation
/*if(packet.header.dataType == TRANSFER_PACKET_TYPE_H264)
{
pkt.duration = vDuration;
}
else*/ if(packet.header.dataType == TRANSFER_PACKET_TYPE_AAC)
{
//pkt.duration = aDuration;
}
in_stream = ifmt_ctx->streams[pkt.stream_index];
out_stream = ofmt_ctx->streams[outStreamIndex];
cn = out_stream->codec;
if(packet.header.dataType == TRANSFER_PACKET_TYPE_AAC)
ret= av_bitstream_filter_filter(aacbsfc, in_stream->codec, NULL, &pkt.data, &pkt.size, packet.data/*pkt.data*/, packet.header.dataLen, pkt.flags & AV_PKT_FLAG_KEY);
if(ret < 0)
{
printf("Failed to execute aac bitstream filter \n\n");
exit(0);
}
//if(packet.header.dataType == TRANSFER_PACKET_TYPE_H264)
// av_bitstream_filter_filter(h264bsfc, in_stream->codec, NULL, &pkt.data, &pkt.size, packet.data/*pkt.data*/, pkt.size, 0);
pkt.flags = 1;
//NOTE : Commented the lines below synced audio and video streams
//av_packet_rescale_ts(&pkt, cn->time_base, out_stream->time_base);
//pkt.pts = av_rescale_q_rnd(pkt.pts, in_stream->time_base, out_stream->time_base, AV_ROUND_NEAR_INF|AV_ROUND_PASS_MINMAX);
//pkt.dts = av_rescale_q_rnd(pkt.dts, in_stream->time_base, out_stream->time_base, AV_ROUND_NEAR_INF|AV_ROUND_PASS_MINMAX);
//pkt.duration = av_rescale_q(pkt.duration, in_stream->time_base, out_stream->time_base);
//enabled on Tuesday
pkt.pos = -1;
pkt.stream_index = outStreamIndex;
//doxygen suggests i use av_write_frame if i am taking care of interleaving
ret = av_interleaved_write_frame(ofmt_ctx, &pkt);
//ret = av_write_frame(ofmt_ctx, &pkt);
if (ret < 0)
{
fprintf(stderr, "Error muxing packet\n");
continue;
}
av_free_packet(&pkt);
if(framebuff != NULL)
{
//printf("Framebuff has mem alloc : freeing 2\n\n");
free(framebuff);
framebuff = NULL;
//printf("Freeing successfully \n\n");
}
} -
Open avi file with OpenCV : ffmpeg ?
28 juin 2012, par CTZStefThis question is related to a previous question I asked here.
I read on the Willow Garage website dedicated to OpenCV that we do not have to take care of ffmpeg while installing OpenCV since version 1.2.x. Here it is.
However, some questions asked here on Stackoverflow suggest the contrary.
So, what should I do ? Do I have to recompile OpenCV and do some special operation related to ffmpeg to get it to, finally, open avi file on my Linux system ?
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