On Jul 23, 2013 11:54 AM, "Marika Marszalkowski" <marika...@gmail.com> wrote: > > I should have added that oformat->video_codec is AV_CODEC_ID_H264, of course. > > Best, > Marika > > > On Mon, Jul 22, 2013 at 8:00 PM, Marika Marszalkowski <marika...@gmail.com> wrote: >> >> Hello everyone, >> >> I have been trying to create an encoded h264 Video from multiple images (QImage), but I can't really achieve this. >> >> This list is my last resort and I totally hope there is someone out there who can help me with this not as complicated problem. I am not sure what the exact problem is - the video is created, but it is kind of jumpy, so that an image is shown and it stays there for two second and then there is a very short sequence (like half a second) and it's not moving again. Also the first 40 encoded frames, return 0 (SUCCESS) but got_packet_ptr is 0. >> >> So this is how I create the video with its header: >> >> AVCodec *codec = avcodec_find_encoder(oformat->video_codec); >> >> >> m_codecContext = avcodec_alloc_context3(codec); >> >> m_codecContext->gop_size = 30; >> >> m_codecContext->sample_fmt = AV_SAMPLE_FMT_NONE; >> >> m_codecContext->bit_rate = width * height; >> >> m_codecContext->width = width; >> >> m_codecContext->height = height; >> >> m_codecContext->time_base = (AVRational){1,frameRate}; >> >> m_codecContext->pix_fmt = AV_PIX_FMT_YUV420P; >> >> >> formatCtx = avformat_alloc_context(); >> >> if(!formatCtx) >> >> { >> >> printf("Error allocating format context\n"); >> >> } >> >> formatCtx->oformat = oformat; >> >> formatCtx->video_codec_id = oformat->video_codec; >> >> snprintf(formatCtx->filename, sizeof(formatCtx->filename), "%s", outputFileName.toStdString().c_str()); >> >> >> AVStream *videoStream = av_new_stream(formatCtx, 0); >> >> if(!videoStream) >> >> { >> >> printf("Could not allocate stream\n"); >> >> } >> >> videoStream->codec = m_codecContext; >> >> >> if(formatCtx->oformat->flags & AVFMT_GLOBALHEADER) >> >> { >> >> m_codecContext->flags |= CODEC_FLAG_GLOBAL_HEADER; >> >> } >> >> >> avcodec_open2(m_codecContext, codec, NULL); >> >> avio_open(&formatCtx->pb, outputFileName.toStdString().c_str(), AVIO_FLAG_WRITE); >> >> avformat_write_header(formatCtx, NULL); >> >> >> >> and this is how I add the frames: >> >> >> >> >> AVFrame *frame = avcodec_alloc_frame(); >> >> int size = m_codecContext->width * m_codecContext->height; >> >> int numBytes = avpicture_get_size(m_codecContext->pix_fmt, m_codecContext->width, m_codecContext->height); >> >> >> QSharedPointer<BlendImage> img = imageData; >> >> >> uint8_t *outbuf = (uint8_t *)malloc(numBytes); >> >> uint8_t *picture_buf = (uint8_t *)av_malloc(numBytes); >> >> >> if (true) >> >> { >> >> int ret = av_image_fill_arrays(frame->data, frame->linesize, picture_buf, m_codecContext->pix_fmt, m_codecContext->width, m_codecContext->height, 1); >> >> >> frame->data[0] = picture_buf; >> >> frame->data[1] = frame->data[0] + size; >> >> frame->data[2] = frame->data[1] + size/4; >> >> frame->linesize[0] = m_codecContext->width; >> >> frame->linesize[1] = m_codecContext->width/2; >> >> frame->linesize[2] = m_codecContext->width/2; >> >> >> fflush(stdout); >> >> for (int y = 0; y < m_codecContext->height; y++) >> >> { >> >> for (int x = 0; x < m_codecContext->width; x++) >> >> { >> >> unsigned char b = img->bits()[(y * m_codecContext->width + x) * 4 + 0]; >> >> unsigned char g = img->bits()[(y * m_codecContext->width + x) * 4 + 1]; >> >> unsigned char r = img->bits()[(y * m_codecContext->width + x) * 4 + 2]; >> >> >> unsigned char Y = (0.257 * r) + (0.504 * g) + (0.098 * b) + 16; >> >> >> frame->data[0][y * frame->linesize[0] + x] = Y; >> >> >> if (y % 2 == 0 && x % 2 == 0) >> >> { >> >> unsigned char V = (0.439 * r) - (0.368 * g) - (0.071 * b) + 128; >> >> unsigned char U = -(0.148 * r) - (0.291 * g) + (0.439 * b) + 128; >> >> >> frame->data[1][y/2 * frame->linesize[1] + x/2] = U; >> >> frame->data[2][y/2 * frame->linesize[2] + x/2] = V; >> >> } >> >> } >> >> } >> >> int pts = (1.0 / 30.0) * 9000.0 * frameIndex; >> >> frame->pts = pts; >> >> >> int got_packet_ptr; >> >> >> AVPacket packet; >> >> av_init_packet(&packet); >> >> packet.data = outbuf; >> >> packet.size = numBytes; >> >> packet.stream_index = formatCtx->streams[0]->index; >> >> packet.flags |= AV_PKT_FLAG_KEY; >> >> packet.pts = packet.dts = pts; >> >> >> m_codecContext->coded_frame->pts = pts; >> >> >> ret = avcodec_encode_video2(m_codecContext, &packet, frame, &got_packet_ptr); >> >> >> >> if (got_packet_ptr != 0) >> >> { >> >> m_codecContext->coded_frame->pts = pts; >> >> >> if (m_codecContext->coded_frame->pts != (0x8000000000000000LL)) >> >> pts = av_rescale_q(m_codecContext->coded_frame->pts, m_codecContext->time_base, formatCtx->streams[0]->time_base); >> >> >> packet.pts = pts; >> >> >> if(m_codecContext->coded_frame->key_frame) >> >> { >> >> packet.flags |= AV_PKT_FLAG_KEY; >> >> } >> >> >> >> std::cout << "pts: " << packet.pts << ", dts: " << packet.dts << std::endl; >> >> >> av_interleaved_write_frame(formatCtx, &packet); >> >> av_free_packet(&packet); >> >> } >> >> } >> >> >> free(picture_buf); >> >> free(outbuf); >> >> av_free(frame); >> >> >> >> and of course in the end: >> >> >> av_write_trailer(formatCtx); >> >> fclose(m_file); >> >> avcodec_close(m_codecContext); >> >> av_free(m_codecContext); >> >> >> >> I think this has something to do with the PTS/DTS values. PTS values start at 120 (as the first 40 frames are omitted) and are increased by 3 ((1.0 / 30.0) * 9000.0 * frameIndex) and the DTS values start at -6 also being increased by 3 per frame. But it might also be the settings or anything else. I feel like I have tried everything I was able to find on the internet and it's still wrong. I am desperate, help would be soooo appreciated! >> >> >> Cheers, >> >> Marika
What is your output format? Alex
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