[FFmpeg-devel] [PATCH 1/4] lavf: add write_uncoded_frame() API.

[Nicolas George]

Signed-off-by: Nicolas George <george at nsup.org>
---
 libavformat/avformat.h |   44 ++++++++++++++++++++++++++++++++++++++++++++
 libavformat/mux.c      |   43 ++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 86 insertions(+), 1 deletion(-)

diff --git a/libavformat/avformat.h b/libavformat/avformat.h
index 6d719d7..9b25bff 100644
--- a/libavformat/avformat.h
+++ b/libavformat/avformat.h
@@ -453,6 +453,14 @@ typedef struct AVOutputFormat {
 
     void (*get_output_timestamp)(struct AVFormatContext *s, int stream,
                                  int64_t *dts, int64_t *wall);
+
+    /**
+     * Write an uncoded AVFrame
+     *
+     * See av_write_uncoded_frame() for details.
+     */
+    int (*write_uncoded_frame)(struct AVFormatContext *, int stream_index,
+                               AVFrame *frame, unsigned flags);
 } AVOutputFormat;
 /**
  * @}
@@ -1908,6 +1916,42 @@ int av_write_frame(AVFormatContext *s, AVPacket *pkt);
 int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt);
 
 /**
+ * Write a uncoded frame to an output media file
+ *
+ * If the muxer supports it, this function allows to write an AVFrame
+ * structure directly, without encoding it into a packet.
+ * It is mostly useful for devices and similar special muxers that use raw
+ * video or PCM data and will not serialize it into a byte stream.
+ *
+ * To test whether it is possible to use it with a given muxer and stream,
+ * use the AV_WRITE_UNCODED_FRAME_QUERY flag with frame = NULL.
+ *
+ * The caller keeps ownership of the frame and is responsible for freeing
+ * it.
+ *
+ * @return  >=0 for success, a negative code on error
+ */
+int av_write_uncoded_frame(AVFormatContext *s, int stream_index,
+                           AVFrame *frame, unsigned flags);
+
+enum AVWriteUncodedFrameFlags {
+
+    /**
+     * Query whether the feature is possible on this stream.
+     * The frame argument is ignored.
+     */
+    AV_WRITE_UNCODED_FRAME_QUERY           = 0x0001,
+
+    /**
+     * Do not queue packets for interleaving.
+     * If this flag is set, the application is responsible for interleaving.
+     */
+    AV_WRITE_UNCODED_FRAME_NO_INTERLEAVE   = 0x0002,
+
+};
+
+
+/**
  * Write the stream trailer to an output media file and free the
  * file private data.
  *
diff --git a/libavformat/mux.c b/libavformat/mux.c
index f01b82b..0ea7dfc 100644
--- a/libavformat/mux.c
+++ b/libavformat/mux.c
@@ -414,6 +414,8 @@ int avformat_write_header(AVFormatContext *s, AVDictionary **options)
     return 0;
 }
 
+#define AV_PKT_FLAG_UNCODED_FRAME 0x2000
+
 //FIXME merge with compute_pkt_fields
 static int compute_pkt_fields2(AVFormatContext *s, AVStream *st, AVPacket *pkt)
 {
@@ -536,7 +538,13 @@ static int write_packet(AVFormatContext *s, AVPacket *pkt)
     }
 
     did_split = av_packet_split_side_data(pkt);
-    ret = s->oformat->write_packet(s, pkt);
+    if ((pkt->flags & AV_PKT_FLAG_UNCODED_FRAME)) {
+        av_assert0(pkt->size == sizeof(AVFrame));
+        ret = s->oformat->write_uncoded_frame(s, pkt->stream_index,
+                                              (AVFrame *)pkt->data, 0);
+    } else {
+        ret = s->oformat->write_packet(s, pkt);
+    }
 
     if (s->flush_packets && s->pb && ret >= 0 && s->flags & AVFMT_FLAG_FLUSH_PACKETS)
         avio_flush(s->pb);
@@ -871,3 +879,36 @@ int ff_write_chained(AVFormatContext *dst, int dst_stream, AVPacket *pkt,
                                           dst->streams[dst_stream]->time_base);
     return av_write_frame(dst, &local_pkt);
 }
+
+int av_write_uncoded_frame(AVFormatContext *s, int stream_index,
+                           AVFrame *frame, unsigned flags)
+{
+    AVPacket pkt, *pktp;
+
+    av_assert0(s->oformat);
+    if (!s->oformat->write_uncoded_frame)
+        return AVERROR(ENOSYS);
+    if ((flags & AV_WRITE_UNCODED_FRAME_QUERY))
+        return s->oformat->write_uncoded_frame(s, stream_index, NULL, flags);
+
+    if (!frame) {
+        pktp = NULL;
+    } else {
+        pktp = &pkt;
+        av_init_packet(&pkt);
+        pkt.data = (void *)frame;
+        /* Note: using sizeof(AVFrame) from outside lavu is unsafe in
+           geneal, but it is only being used internally to this file as a
+           consistency check. */
+        pkt.size         = sizeof(*frame);
+        pkt.pts          = frame->pts != AV_NOPTS_VALUE ? frame->pts : frame->pkt_pts;
+        pkt.dts          = frame->pkt_dts;
+        pkt.duration     = av_frame_get_pkt_duration(frame);
+        pkt.stream_index = stream_index;
+        pkt.flags |= AV_PKT_FLAG_UNCODED_FRAME;
+    }
+
+    return (flags & AV_WRITE_UNCODED_FRAME_NO_INTERLEAVE) ?
+           av_write_frame(s, pktp) :
+           av_interleaved_write_frame(s, pktp);
+}
-- 
1.7.10.4