| Message ID | 1590512230-26007-1-git-send-email-mypopydev@gmail.com |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [FFmpeg-devel,v2,1/4] lavc/aac_ac3_parser: improve the raw AAC file bit rate calculation | expand |
| Context | Check | Description |
|---|---|---|
| andriy/default | pending | |
| andriy/make | success | Make finished |
| andriy/make_fate | success | Make fate finished |
On Wed, May 27, 2020 at 12:57 AM Jun Zhao <mypopydev@gmail.com> wrote: > > From: Jun Zhao <barryjzhao@tencent.com> > > Now we just use one ADTS raw frame to calculate the bit rate, it's > lead to a larger error when get the duration from bit rate, the > improvement cumulate Nth ADTS frames to get the average bit rate. > > e,g used the command get the duration like: > ffprobe -show_entries format=duration -i fate-suite/aac/foo.aac > > before this improvement dump the duration=2.173935 > after this improvement dump the duration=1.979267 > > in fact, the real duration can be get by command like: > ffmpeg -i fate-suite/aac/foo.aac -f null /dev/null with time=00:00:01.97 > > Also update the fate-adtstoasc_ticket3715. > > Signed-off-by: Jun Zhao <barryjzhao@tencent.com> > --- > libavcodec/aac_ac3_parser.c | 9 +++++++-- > libavcodec/aac_ac3_parser.h | 2 ++ > tests/ref/fate/adtstoasc_ticket3715 | 2 +- > 3 files changed, 10 insertions(+), 3 deletions(-) > > diff --git a/libavcodec/aac_ac3_parser.c b/libavcodec/aac_ac3_parser.c > index 54e4598..0746798 100644 > --- a/libavcodec/aac_ac3_parser.c > +++ b/libavcodec/aac_ac3_parser.c > @@ -97,8 +97,13 @@ get_next: > avctx->audio_service_type = s->service_type; > } > > - if (avctx->codec_id != AV_CODEC_ID_EAC3) > - avctx->bit_rate = s->bit_rate; > + /* Calculate the average bit rate */ > + s->frame_number++; > + if (avctx->codec_id != AV_CODEC_ID_EAC3) { > + avctx->bit_rate = > + (s->last_bit_rate * (s->frame_number -1) + s->bit_rate)/s->frame_number; > + s->last_bit_rate = avctx->bit_rate; > + } > } > > return i; > diff --git a/libavcodec/aac_ac3_parser.h b/libavcodec/aac_ac3_parser.h > index c2506a5..b04041f 100644 > --- a/libavcodec/aac_ac3_parser.h > +++ b/libavcodec/aac_ac3_parser.h > @@ -55,6 +55,8 @@ typedef struct AACAC3ParseContext { > uint64_t state; > > int need_next_header; > + int frame_number; > + int last_bit_rate; > enum AVCodecID codec_id; > } AACAC3ParseContext; > > diff --git a/tests/ref/fate/adtstoasc_ticket3715 b/tests/ref/fate/adtstoasc_ticket3715 > index 49fa3eb..3b473ee 100644 > --- a/tests/ref/fate/adtstoasc_ticket3715 > +++ b/tests/ref/fate/adtstoasc_ticket3715 > @@ -1,4 +1,4 @@ > -4110be924e21846d0e174fac679b062e *tests/data/fate/adtstoasc_ticket3715.mov > +3e63cbb6bb6ec756d79fab2632fef305 *tests/data/fate/adtstoasc_ticket3715.mov > 33324 tests/data/fate/adtstoasc_ticket3715.mov > #extradata 0: 2, 0x00340022 > #tb 0: 1/44100 > -- > 2.7.4 Ping
diff --git a/libavcodec/aac_ac3_parser.c b/libavcodec/aac_ac3_parser.c index 54e4598..0746798 100644 --- a/libavcodec/aac_ac3_parser.c +++ b/libavcodec/aac_ac3_parser.c @@ -97,8 +97,13 @@ get_next: avctx->audio_service_type = s->service_type; } - if (avctx->codec_id != AV_CODEC_ID_EAC3) - avctx->bit_rate = s->bit_rate; + /* Calculate the average bit rate */ + s->frame_number++; + if (avctx->codec_id != AV_CODEC_ID_EAC3) { + avctx->bit_rate = + (s->last_bit_rate * (s->frame_number -1) + s->bit_rate)/s->frame_number; + s->last_bit_rate = avctx->bit_rate; + } } return i; diff --git a/libavcodec/aac_ac3_parser.h b/libavcodec/aac_ac3_parser.h index c2506a5..b04041f 100644 --- a/libavcodec/aac_ac3_parser.h +++ b/libavcodec/aac_ac3_parser.h @@ -55,6 +55,8 @@ typedef struct AACAC3ParseContext { uint64_t state; int need_next_header; + int frame_number; + int last_bit_rate; enum AVCodecID codec_id; } AACAC3ParseContext; diff --git a/tests/ref/fate/adtstoasc_ticket3715 b/tests/ref/fate/adtstoasc_ticket3715 index 49fa3eb..3b473ee 100644 --- a/tests/ref/fate/adtstoasc_ticket3715 +++ b/tests/ref/fate/adtstoasc_ticket3715 @@ -1,4 +1,4 @@ -4110be924e21846d0e174fac679b062e *tests/data/fate/adtstoasc_ticket3715.mov +3e63cbb6bb6ec756d79fab2632fef305 *tests/data/fate/adtstoasc_ticket3715.mov 33324 tests/data/fate/adtstoasc_ticket3715.mov #extradata 0: 2, 0x00340022 #tb 0: 1/44100