static int yuv4_write_packet(AVFormatContext *s, AVPacket *pkt) { AVStream *st = s->streams[pkt->stream_index]; AVIOContext *pb = s->pb; AVFrame *frame; int* first_pkt = s->priv_data; int width, height, h_chroma_shift, v_chroma_shift; int i; char buf2[Y4M_LINE_MAX + 1]; uint8_t *ptr, *ptr1, *ptr2; frame = (AVFrame *)pkt->data; /* for the first packet we have to output the header as well */ if (*first_pkt) { *first_pkt = 0; if (yuv4_generate_header(s, buf2) < 0) { av_log(s, AV_LOG_ERROR, "Error. YUV4MPEG stream header write failed.\n"); return AVERROR(EIO); } else { avio_write(pb, buf2, strlen(buf2)); } } /* construct frame header */ avio_printf(s->pb, "%s\n", Y4M_FRAME_MAGIC); width = st->codecpar->width; height = st->codecpar->height; ptr = frame->data[0]; switch (st->codecpar->format) { case AV_PIX_FMT_GRAY8: case AV_PIX_FMT_YUV411P: case AV_PIX_FMT_YUV420P: case AV_PIX_FMT_YUV422P: case AV_PIX_FMT_YUV444P: break; case AV_PIX_FMT_GRAY16: case AV_PIX_FMT_YUV420P9: case AV_PIX_FMT_YUV422P9: case AV_PIX_FMT_YUV444P9: case AV_PIX_FMT_YUV420P10: case AV_PIX_FMT_YUV422P10: case AV_PIX_FMT_YUV444P10: case AV_PIX_FMT_YUV420P12: case AV_PIX_FMT_YUV422P12: case AV_PIX_FMT_YUV444P12: case AV_PIX_FMT_YUV420P14: case AV_PIX_FMT_YUV422P14: case AV_PIX_FMT_YUV444P14: case AV_PIX_FMT_YUV420P16: case AV_PIX_FMT_YUV422P16: case AV_PIX_FMT_YUV444P16: width *= 2; break; default: av_log(s, AV_LOG_ERROR, "The pixel format '%s' is not supported.\n", av_get_pix_fmt_name(st->codecpar->format)); return AVERROR(EINVAL); } for (i = 0; i < height; i++) { avio_write(pb, ptr, width); ptr += frame->linesize[0]; } if (st->codecpar->format != AV_PIX_FMT_GRAY8 && st->codecpar->format != AV_PIX_FMT_GRAY16) { // Adjust for smaller Cb and Cr planes av_pix_fmt_get_chroma_sub_sample(st->codecpar->format, &h_chroma_shift, &v_chroma_shift); // Shift right, rounding up width = AV_CEIL_RSHIFT(width, h_chroma_shift); height = AV_CEIL_RSHIFT(height, v_chroma_shift); ptr1 = frame->data[1]; ptr2 = frame->data[2]; for (i = 0; i < height; i++) { /* Cb */ avio_write(pb, ptr1, width); ptr1 += frame->linesize[1]; } for (i = 0; i < height; i++) { /* Cr */ avio_write(pb, ptr2, width); ptr2 += frame->linesize[2]; } } return 0; }