On Tue, 22 Oct 2024, Anton Khirnov wrote:
Quoting Martin Schitter (2024-10-21 21:57:18)+static int pass_through(AVCodecContext *avctx, AVFrame *frame, const AVPacket *avpkt) +{ + /* there is no need to copy as the data already match + * a known pixel format */ + + frame->buf[0] = av_buffer_ref(avpkt->buf);I said this twice before already - every single format that uses pass_through() should instead be exported by the demuxer as AV_CODEC_ID_RAWVIDEO, because that's what it is.
I don't really want the MXF demuxer/muxer to do DNXUC parsing or creation. Also I might want to wrap DNXUC essence to another container, or remux it to MXF again. So I am not convinced that the current approach is bad.
Regards, Marton
That will also have the following important advantages: * decoding these formats won't pointlessly waste resources and add latency using frame threading, which is useless for them * your decoder can be marked as AV_CODEC_CAP_DR1+static int unpack_y212(AVCodecContext *avctx, AVFrame *frame, const AVPacket *pkt) +{ + uint8_t *data = &pkt->data[0]; + int lw = frame->width; + int msb_bytes = lw * 2; + int line_offset = lw * 3; + int pos_uv = 0, pos_y = 0, pos_in = 0; + for(int y = 0; y < frame->height; y++){ + for(int x = 0; x < lw/2; x++){ + AV_WL16(&frame->data[1][pos_uv], get12(data, pos_in++, msb_bytes)); // u + AV_WL16(&frame->data[0][pos_y], get12(data, pos_in++, msb_bytes)); // y + AV_WL16(&frame->data[2][pos_uv], get12(data, pos_in++, msb_bytes)); // v + AV_WL16(&frame->data[0][pos_y + 2],get12(data, pos_in++, msb_bytes)); // y + pos_uv += 2; + pos_y += 4; + } + data += line_offset; + pos_in = 0; + } + return pkt->size; +}These functions are now MUCH more readable, and it becomes clear that you're not accessing frame->linesize, which is immensely suspicious. Lines of a frame do not need to be contiguous in memory, there can be arbitrary amounts of paddding between them. -- Anton Khirnov _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
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