diff mbox series

[FFmpeg-devel,v2,7/9] avformat/pcm: factorize and improve determining the default packet size

Message ID 20240308005333.12416-7-cus@passwd.hu
State New
Headers show
Series [FFmpeg-devel,v2,1/9] avcodec/bsf/pcm_rechunk: reorder supported codec list | expand

Checks

Context Check Description
andriy/make_x86 success Make finished
andriy/make_fate_x86 success Make fate finished
yinshiyou/make_loongarch64 success Make finished
yinshiyou/make_fate_loongarch64 success Make fate finished

Commit Message

Marton Balint March 8, 2024, 12:53 a.m. UTC 
- Remove the 1024 cap on the number of samples, for high sample rate audio it
  was suboptimal, calculate the low neighbour power of two for the number of
  samples (audio blocks) instead.
- Make the function work correctly for non-pcm codecs by using
  av_get_audio_frame_duration2() to esimate the packet duration for a given
  size
- Fall back to 4096/block_align if av_get_audio_frame_duration2() is not
  supported

Signed-off-by: Marton Balint <cus@passwd.hu>
---
 libavformat/pcm.c      | 42 ++++++++++++++++++++++++++------------
 libavformat/pcm.h      |  1 +
 tests/ref/seek/lavf-al | 46 +++++++++++++++++++++---------------------
 tests/ref/seek/lavf-ul | 46 +++++++++++++++++++++---------------------
 4 files changed, 76 insertions(+), 59 deletions(-)

Comments

Marton Balint March 12, 2024, 9:31 p.m. UTC | #1 
On Fri, 8 Mar 2024, Marton Balint wrote:

> - Remove the 1024 cap on the number of samples, for high sample rate audio it
>  was suboptimal, calculate the low neighbour power of two for the number of
>  samples (audio blocks) instead.
> - Make the function work correctly for non-pcm codecs by using
>  av_get_audio_frame_duration2() to esimate the packet duration for a given
>  size
> - Fall back to 4096/block_align if av_get_audio_frame_duration2() is not
>  supported

Will apply this series soon.

Regards,
Marton
diff mbox series

Patch

diff --git a/libavformat/pcm.c b/libavformat/pcm.c
index 9741f73667..b7728dd15e 100644
--- a/libavformat/pcm.c
+++ b/libavformat/pcm.c
@@ -19,32 +19,48 @@ 
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
+#include "libavcodec/codec_par.h"
 #include "libavutil/mathematics.h"
 #include "avformat.h"
 #include "internal.h"
 #include "pcm.h"
 
-#define RAW_SAMPLES     1024
+#define PCM_DEMUX_TARGET_FPS  25
 
-int ff_pcm_read_packet(AVFormatContext *s, AVPacket *pkt)
+int ff_pcm_default_packet_size(AVCodecParameters *par)
 {
-    AVCodecParameters *par = s->streams[0]->codecpar;
-    int ret, size;
+    int nb_samples, max_samples, target_duration;
 
     if (par->block_align <= 0)
         return AVERROR(EINVAL);
 
-    /*
-     * Compute read size to complete a read every 62ms.
-     * Clamp to RAW_SAMPLES if larger.
-     */
-    size = FFMAX(par->sample_rate/25, 1);
-    if (par->block_align <= INT_MAX / RAW_SAMPLES) {
-        size = FFMIN(size, RAW_SAMPLES) * par->block_align;
-    } else {
-        size = par->block_align;
+    max_samples = INT_MAX / par->block_align;
+    target_duration = FFMAX(1, par->sample_rate / PCM_DEMUX_TARGET_FPS);
+    nb_samples = 1 << av_log2(FFMIN(target_duration, max_samples));
+
+    while (nb_samples > 1) {
+        int duration = av_get_audio_frame_duration2(par, par->block_align * nb_samples);
+        if (!duration) {
+            /* Fallback to a size based method for a likely non-pcm codec */
+            nb_samples = av_clip(4096 / par->block_align, 1, max_samples);
+            break;
+        }
+        if (duration <= target_duration)
+            break;
+        nb_samples >>= 1;
     }
 
+    return par->block_align * nb_samples;
+}
+
+int ff_pcm_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    int ret, size;
+
+    size = ff_pcm_default_packet_size(s->streams[0]->codecpar);
+    if (size < 0)
+        return size;
+
     ret = av_get_packet(s->pb, pkt, size);
 
     pkt->flags &= ~AV_PKT_FLAG_CORRUPT;
diff --git a/libavformat/pcm.h b/libavformat/pcm.h
index 9af36d5a2e..1928497eed 100644
--- a/libavformat/pcm.h
+++ b/libavformat/pcm.h
@@ -24,6 +24,7 @@ 
 
 #include "avformat.h"
 
+int ff_pcm_default_packet_size(AVCodecParameters *par);
 int ff_pcm_read_packet(AVFormatContext *s, AVPacket *pkt);
 int ff_pcm_read_seek(AVFormatContext *s,
                      int stream_index, int64_t timestamp, int flags);
diff --git a/tests/ref/seek/lavf-al b/tests/ref/seek/lavf-al
index 5a4085af4e..ebf7993425 100644
--- a/tests/ref/seek/lavf-al
+++ b/tests/ref/seek/lavf-al
@@ -1,50 +1,50 @@ 
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   882
+ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   512
 ret: 0         st:-1 flags:0  ts:-1.000000
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   882
+ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   512
 ret: 0         st:-1 flags:1  ts: 1.894167
-ret: 0         st: 0 flags:1 dts: 1.894150 pts: 1.894150 pos:  41766 size:   882
+ret: 0         st: 0 flags:1 dts: 1.894150 pts: 1.894150 pos:  41766 size:   512
 ret: 0         st: 0 flags:0  ts: 0.788345
-ret: 0         st: 0 flags:1 dts: 0.788345 pts: 0.788345 pos:  17383 size:   882
+ret: 0         st: 0 flags:1 dts: 0.788345 pts: 0.788345 pos:  17383 size:   512
 ret: 0         st: 0 flags:1  ts:-0.317506
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   882
+ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   512
 ret:-1         st:-1 flags:0  ts: 2.576668
 ret: 0         st:-1 flags:1  ts: 1.470835
-ret: 0         st: 0 flags:1 dts: 1.470839 pts: 1.470839 pos:  32432 size:   882
+ret: 0         st: 0 flags:1 dts: 1.470839 pts: 1.470839 pos:  32432 size:   512
 ret: 0         st: 0 flags:0  ts: 0.364989
-ret: 0         st: 0 flags:1 dts: 0.364989 pts: 0.364989 pos:   8048 size:   882
+ret: 0         st: 0 flags:1 dts: 0.364989 pts: 0.364989 pos:   8048 size:   512
 ret: 0         st: 0 flags:1  ts:-0.740816
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   882
+ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   512
 ret:-1         st:-1 flags:0  ts: 2.153336
 ret: 0         st:-1 flags:1  ts: 1.047503
-ret: 0         st: 0 flags:1 dts: 1.047483 pts: 1.047483 pos:  23097 size:   882
+ret: 0         st: 0 flags:1 dts: 1.047483 pts: 1.047483 pos:  23097 size:   512
 ret: 0         st: 0 flags:0  ts:-0.058322
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   882
+ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   512
 ret: 0         st: 0 flags:1  ts: 2.835828
-ret: 0         st: 0 flags:1 dts: 1.960000 pts: 1.960000 pos:  43218 size:   882
+ret: 0         st: 0 flags:1 dts: 1.987029 pts: 1.987029 pos:  43814 size:   286
 ret: 0         st:-1 flags:0  ts: 1.730004
-ret: 0         st: 0 flags:1 dts: 1.730023 pts: 1.730023 pos:  38147 size:   882
+ret: 0         st: 0 flags:1 dts: 1.730023 pts: 1.730023 pos:  38147 size:   512
 ret: 0         st:-1 flags:1  ts: 0.624171
-ret: 0         st: 0 flags:1 dts: 0.624172 pts: 0.624172 pos:  13763 size:   882
+ret: 0         st: 0 flags:1 dts: 0.624172 pts: 0.624172 pos:  13763 size:   512
 ret: 0         st: 0 flags:0  ts:-0.481678
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   882
+ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   512
 ret: 0         st: 0 flags:1  ts: 2.412517
-ret: 0         st: 0 flags:1 dts: 1.960000 pts: 1.960000 pos:  43218 size:   882
+ret: 0         st: 0 flags:1 dts: 1.987029 pts: 1.987029 pos:  43814 size:   286
 ret: 0         st:-1 flags:0  ts: 1.306672
-ret: 0         st: 0 flags:1 dts: 1.306667 pts: 1.306667 pos:  28812 size:   882
+ret: 0         st: 0 flags:1 dts: 1.306667 pts: 1.306667 pos:  28812 size:   512
 ret: 0         st:-1 flags:1  ts: 0.200839
-ret: 0         st: 0 flags:1 dts: 0.200816 pts: 0.200816 pos:   4428 size:   882
+ret: 0         st: 0 flags:1 dts: 0.200816 pts: 0.200816 pos:   4428 size:   512
 ret: 0         st: 0 flags:0  ts:-0.904989
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   882
+ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   512
 ret: 0         st: 0 flags:1  ts: 1.989161
 ret: 0         st: 0 flags:1 dts: 1.989161 pts: 1.989161 pos:  43861 size:   239
 ret: 0         st:-1 flags:0  ts: 0.883340
-ret: 0         st: 0 flags:1 dts: 0.883356 pts: 0.883356 pos:  19478 size:   882
+ret: 0         st: 0 flags:1 dts: 0.883356 pts: 0.883356 pos:  19478 size:   512
 ret: 0         st:-1 flags:1  ts:-0.222493
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   882
+ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   512
 ret:-1         st: 0 flags:0  ts: 2.671655
 ret: 0         st: 0 flags:1  ts: 1.565850
-ret: 0         st: 0 flags:1 dts: 1.565850 pts: 1.565850 pos:  34527 size:   882
+ret: 0         st: 0 flags:1 dts: 1.565850 pts: 1.565850 pos:  34527 size:   512
 ret: 0         st:-1 flags:0  ts: 0.460008
-ret: 0         st: 0 flags:1 dts: 0.460000 pts: 0.460000 pos:  10143 size:   882
+ret: 0         st: 0 flags:1 dts: 0.460000 pts: 0.460000 pos:  10143 size:   512
 ret: 0         st:-1 flags:1  ts:-0.645825
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   882
+ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   512
diff --git a/tests/ref/seek/lavf-ul b/tests/ref/seek/lavf-ul
index 5a4085af4e..ebf7993425 100644
--- a/tests/ref/seek/lavf-ul
+++ b/tests/ref/seek/lavf-ul
@@ -1,50 +1,50 @@ 
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   882
+ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   512
 ret: 0         st:-1 flags:0  ts:-1.000000
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   882
+ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   512
 ret: 0         st:-1 flags:1  ts: 1.894167
-ret: 0         st: 0 flags:1 dts: 1.894150 pts: 1.894150 pos:  41766 size:   882
+ret: 0         st: 0 flags:1 dts: 1.894150 pts: 1.894150 pos:  41766 size:   512
 ret: 0         st: 0 flags:0  ts: 0.788345
-ret: 0         st: 0 flags:1 dts: 0.788345 pts: 0.788345 pos:  17383 size:   882
+ret: 0         st: 0 flags:1 dts: 0.788345 pts: 0.788345 pos:  17383 size:   512
 ret: 0         st: 0 flags:1  ts:-0.317506
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   882
+ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   512
 ret:-1         st:-1 flags:0  ts: 2.576668
 ret: 0         st:-1 flags:1  ts: 1.470835
-ret: 0         st: 0 flags:1 dts: 1.470839 pts: 1.470839 pos:  32432 size:   882
+ret: 0         st: 0 flags:1 dts: 1.470839 pts: 1.470839 pos:  32432 size:   512
 ret: 0         st: 0 flags:0  ts: 0.364989
-ret: 0         st: 0 flags:1 dts: 0.364989 pts: 0.364989 pos:   8048 size:   882
+ret: 0         st: 0 flags:1 dts: 0.364989 pts: 0.364989 pos:   8048 size:   512
 ret: 0         st: 0 flags:1  ts:-0.740816
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   882
+ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   512
 ret:-1         st:-1 flags:0  ts: 2.153336
 ret: 0         st:-1 flags:1  ts: 1.047503
-ret: 0         st: 0 flags:1 dts: 1.047483 pts: 1.047483 pos:  23097 size:   882
+ret: 0         st: 0 flags:1 dts: 1.047483 pts: 1.047483 pos:  23097 size:   512
 ret: 0         st: 0 flags:0  ts:-0.058322
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   882
+ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   512
 ret: 0         st: 0 flags:1  ts: 2.835828
-ret: 0         st: 0 flags:1 dts: 1.960000 pts: 1.960000 pos:  43218 size:   882
+ret: 0         st: 0 flags:1 dts: 1.987029 pts: 1.987029 pos:  43814 size:   286
 ret: 0         st:-1 flags:0  ts: 1.730004
-ret: 0         st: 0 flags:1 dts: 1.730023 pts: 1.730023 pos:  38147 size:   882
+ret: 0         st: 0 flags:1 dts: 1.730023 pts: 1.730023 pos:  38147 size:   512
 ret: 0         st:-1 flags:1  ts: 0.624171
-ret: 0         st: 0 flags:1 dts: 0.624172 pts: 0.624172 pos:  13763 size:   882
+ret: 0         st: 0 flags:1 dts: 0.624172 pts: 0.624172 pos:  13763 size:   512
 ret: 0         st: 0 flags:0  ts:-0.481678
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   882
+ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   512
 ret: 0         st: 0 flags:1  ts: 2.412517
-ret: 0         st: 0 flags:1 dts: 1.960000 pts: 1.960000 pos:  43218 size:   882
+ret: 0         st: 0 flags:1 dts: 1.987029 pts: 1.987029 pos:  43814 size:   286
 ret: 0         st:-1 flags:0  ts: 1.306672
-ret: 0         st: 0 flags:1 dts: 1.306667 pts: 1.306667 pos:  28812 size:   882
+ret: 0         st: 0 flags:1 dts: 1.306667 pts: 1.306667 pos:  28812 size:   512
 ret: 0         st:-1 flags:1  ts: 0.200839
-ret: 0         st: 0 flags:1 dts: 0.200816 pts: 0.200816 pos:   4428 size:   882
+ret: 0         st: 0 flags:1 dts: 0.200816 pts: 0.200816 pos:   4428 size:   512
 ret: 0         st: 0 flags:0  ts:-0.904989
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   882
+ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   512
 ret: 0         st: 0 flags:1  ts: 1.989161
 ret: 0         st: 0 flags:1 dts: 1.989161 pts: 1.989161 pos:  43861 size:   239
 ret: 0         st:-1 flags:0  ts: 0.883340
-ret: 0         st: 0 flags:1 dts: 0.883356 pts: 0.883356 pos:  19478 size:   882
+ret: 0         st: 0 flags:1 dts: 0.883356 pts: 0.883356 pos:  19478 size:   512
 ret: 0         st:-1 flags:1  ts:-0.222493
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   882
+ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   512
 ret:-1         st: 0 flags:0  ts: 2.671655
 ret: 0         st: 0 flags:1  ts: 1.565850
-ret: 0         st: 0 flags:1 dts: 1.565850 pts: 1.565850 pos:  34527 size:   882
+ret: 0         st: 0 flags:1 dts: 1.565850 pts: 1.565850 pos:  34527 size:   512
 ret: 0         st:-1 flags:0  ts: 0.460008
-ret: 0         st: 0 flags:1 dts: 0.460000 pts: 0.460000 pos:  10143 size:   882
+ret: 0         st: 0 flags:1 dts: 0.460000 pts: 0.460000 pos:  10143 size:   512
 ret: 0         st:-1 flags:1  ts:-0.645825
-ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   882
+ret: 0         st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos:      0 size:   512