[FFmpeg-cvslog] avcodec/mpeg4video: Detect reference studio streams as studio streams
Michael Niedermayer
git at videolan.org
Sat Jun 16 01:31:50 EEST 2018
ffmpeg | branch: release/4.0 | Michael Niedermayer <michael at niedermayer.cc> | Sun Apr 29 23:39:41 2018 +0200| [8229afc3a93cb7ad3a812ddb747b74d6775895da] | committer: Michael Niedermayer
avcodec/mpeg4video: Detect reference studio streams as studio streams
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit ba97d75ac6254db90c64d3c7aacdd0548dca7b24)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=8229afc3a93cb7ad3a812ddb747b74d6775895da
---
libavcodec/mpeg4video.h | 2 ++
libavcodec/mpeg4videodec.c | 32 +++++++++++++++++++++++---------
2 files changed, 25 insertions(+), 9 deletions(-)
diff --git a/libavcodec/mpeg4video.h b/libavcodec/mpeg4video.h
index f974792887..dd0a59038d 100644
--- a/libavcodec/mpeg4video.h
+++ b/libavcodec/mpeg4video.h
@@ -41,6 +41,8 @@
#define NBIT_VO_TYPE 5
#define ARTS_VO_TYPE 10
#define ACE_VO_TYPE 12
+#define SIMPLE_STUDIO_VO_TYPE 14
+#define CORE_STUDIO_VO_TYPE 15
#define ADV_SIMPLE_VO_TYPE 17
#define VOT_VIDEO_ID 1
diff --git a/libavcodec/mpeg4videodec.c b/libavcodec/mpeg4videodec.c
index ada5cdc6fa..51b58fac02 100644
--- a/libavcodec/mpeg4videodec.c
+++ b/libavcodec/mpeg4videodec.c
@@ -46,6 +46,8 @@
#define MB_TYPE_B_VLC_BITS 4
#define STUDIO_INTRA_BITS 9
+static int decode_studio_vol_header(Mpeg4DecContext *ctx, GetBitContext *gb);
+
static VLC dc_lum, dc_chrom;
static VLC sprite_trajectory;
static VLC mb_type_b_vlc;
@@ -2049,6 +2051,23 @@ static int decode_vol_header(Mpeg4DecContext *ctx, GetBitContext *gb)
/* vol header */
skip_bits(gb, 1); /* random access */
s->vo_type = get_bits(gb, 8);
+
+ /* If we are in studio profile (per vo_type), check if its all consistent
+ * and if so continue pass control to decode_studio_vol_header().
+ * elIf something is inconsistent, error out
+ * else continue with (non studio) vol header decpoding.
+ */
+ if (s->vo_type == CORE_STUDIO_VO_TYPE ||
+ s->vo_type == SIMPLE_STUDIO_VO_TYPE) {
+ if (s->avctx->profile != FF_PROFILE_UNKNOWN && s->avctx->profile != FF_PROFILE_MPEG4_SIMPLE_STUDIO)
+ return AVERROR_INVALIDDATA;
+ s->studio_profile = 1;
+ s->avctx->profile = FF_PROFILE_MPEG4_SIMPLE_STUDIO;
+ return decode_studio_vol_header(ctx, gb);
+ } else if (s->studio_profile) {
+ return AVERROR_PATCHWELCOME;
+ }
+
if (get_bits1(gb) != 0) { /* is_ol_id */
vo_ver_id = get_bits(gb, 4); /* vo_ver_id */
skip_bits(gb, 3); /* vo_priority */
@@ -3001,8 +3020,8 @@ static int decode_studio_vol_header(Mpeg4DecContext *ctx, GetBitContext *gb)
int width, height;
int bits_per_raw_sample;
- skip_bits1(gb); /* random_accessible_vol */
- skip_bits(gb, 8); /* video_object_type_indication */
+ // random_accessible_vol and video_object_type_indication have already
+ // been read by the caller decode_vol_header()
skip_bits(gb, 4); /* video_object_layer_verid */
ctx->shape = get_bits(gb, 2); /* video_object_layer_shape */
skip_bits(gb, 4); /* video_object_layer_shape_extension */
@@ -3179,13 +3198,8 @@ int ff_mpeg4_decode_picture_header(Mpeg4DecContext *ctx, GetBitContext *gb)
continue;
}
vol++;
- if (s->studio_profile) {
- if ((ret = decode_studio_vol_header(ctx, gb)) < 0)
- return ret;
- } else {
- if ((ret = decode_vol_header(ctx, gb)) < 0)
- return ret;
- }
+ if ((ret = decode_vol_header(ctx, gb)) < 0)
+ return ret;
} else if (startcode == USER_DATA_STARTCODE) {
decode_user_data(ctx, gb);
} else if (startcode == GOP_STARTCODE) {
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