demux, vd_ffmpeg: fix demux keyframe flag, set AV_PKT_FLAG_KEY

There was some confusion about the "flags" field in demuxer packets.
Demuxers set it to either 1 or 0x10 to indicate a keyframe (and the
field was not used to indicate anything else). This didn't cause
visible problems because nothing read the value. Replace the "flags"
field with a boolean "keyframe" field. Set AV_PKT_FLAG_KEY based on
this field in packets fed to libavcodec video decoders (looks like PNG
and ZeroCodec are the only ones which depend on values from demuxer;
previously this was hardcoded to true for PNG).

Make demux_mf set the keyframe field in every packet. This matters for
PNG files now that the demuxer flag is forwarded to libavcodec.

Fix logic setting the field in demux_mkv. It had probably not been
updated when adding SimpleBlock support. This probably makes no
difference for any current practical use.

1 files changed, 2 insertions, 2 deletions

diff --git a/libmpdemux/demuxer.h b/libmpdemux/demuxer.h
index cdea5baa61..24b4edac19 100644
--- a/libmpdemux/demuxer.h
+++ b/libmpdemux/demuxer.h
@@ -135,7 +135,7 @@ typedef struct demux_stream {
     off_t pos;               // position in the input stream (file)
     off_t dpos;              // position in the demuxed stream
     int pack_no;           // serial number of packet
-    int flags;             // flags of current packet (keyframe etc)
+    bool keyframe;         // keyframe flag of current packet
     int non_interleaved;   // 1 if this stream is not properly interleaved,
                            // so e.g. subtitle handling must do explicit reads.
 //---------------
@@ -315,7 +315,7 @@ void free_demuxer(struct demuxer *demuxer);
 
 void ds_add_packet(struct demux_stream *ds, struct demux_packet *dp);
 void ds_read_packet(struct demux_stream *ds, struct stream *stream, int len,
-                    double pts, off_t pos, int flags);
+                    double pts, off_t pos, bool keyframe);
 
 int demux_fill_buffer(struct demuxer *demux, struct demux_stream *ds);
 int ds_fill_buffer(struct demux_stream *ds);