| Message ID | b3a9a2a8-f8f6-0a52-123f-d23097f3851c@davyandbeth.com |
|---|---|
| State | New |
| Headers | show |
| Series | [FFmpeg-devel] fftools/ffmpeg: Added ability to set a input burst time before readrate is enforced | expand |
| Context | Check | Description |
|---|---|---|
| yinshiyou/configure_loongarch64 | warning | Failed to apply patch |
| andriy/configure_x86 | warning | Failed to apply patch |
Apologies.. ignore this patch, it was accidentally incomplete. Complete patch on the way. On 4/7/23 02:50, Davy Durham wrote: > Implemented is the -irb <seconds> flag (i.e. "initial read burst") that > causes ffmpeg to read the specified number of seconds of input before a > given readrate starts to be enforced. All inputs have to reach this > point before the readrate is enforced. The reason for this change is, > in the scenario of live-streaming by transcoding from an pre-recorded or > delayed source to an HLS or DASH webroot, we can more quickly prime the > system of the first few seconds before the real-world read rate is > imposed. Else, one must wait for an entire segment length before the > data can be fetched from the web server. > > Signed-off-by: Davy Durham <ddurham@users.sourceforge.net> > --- > doc/ffmpeg.texi | 2 ++ > fftools/ffmpeg.h | 2 ++ > fftools/ffmpeg_opt.c | 3 +++ > 3 files changed, 7 insertions(+) > > diff --git a/doc/ffmpeg.texi b/doc/ffmpeg.texi > index d433d60ce9..a519fea192 100644 > --- a/doc/ffmpeg.texi > +++ b/doc/ffmpeg.texi > @@ -1709,6 +1709,8 @@ it may cause packet loss. > It is useful for when flow speed of output packets is important, such > as live streaming. > @item -re (@emph{input}) > Read input at native frame rate. This is equivalent to setting > @code{-readrate 1}. > +@item -irb @var{seconds} > +Set an initial read burst time, in seconds, after which any specified > readrate will be enforced. > @item -vsync @var{parameter} (@emph{global}) > @itemx -fps_mode[:@var{stream_specifier}] @var{parameter} > (@emph{output,per-stream}) > Set video sync method / framerate mode. vsync is applied to all > output video streams > diff --git a/fftools/ffmpeg.h b/fftools/ffmpeg.h > index 823218e214..e057e6da3a 100644 > --- a/fftools/ffmpeg.h > +++ b/fftools/ffmpeg.h > @@ -124,6 +124,7 @@ typedef struct OptionsContext { > int loop; > int rate_emu; > float readrate; > + double initial_read_burst; > int accurate_seek; > int thread_queue_size; > int input_sync_ref; > @@ -475,6 +476,7 @@ typedef struct InputFile { > int rate_emu; > float readrate; > + double initial_read_burst; > int accurate_seek; > /* when looping the input file, this queue is used by decoders > to report > diff --git a/fftools/ffmpeg_opt.c b/fftools/ffmpeg_opt.c > index 055275d813..6c55b6cb01 100644 > --- a/fftools/ffmpeg_opt.c > +++ b/fftools/ffmpeg_opt.c > @@ -1443,6 +1443,9 @@ const OptionDef options[] = { > { "readrate", HAS_ARG | OPT_FLOAT | OPT_OFFSET | > OPT_EXPERT | OPT_INPUT, > { .off = OFFSET(readrate) }, > "read input at specified rate", "speed" }, > + { "irb", HAS_ARG | OPT_DOUBLE | OPT_OFFSET | > + OPT_EXPERT | OPT_INPUT, > { .off = OFFSET(initial_read_burst) }, > + "The initial amount of input to burst read before imposing > any readrate", "seconds" }, > { "target", HAS_ARG | OPT_PERFILE | OPT_OUTPUT, > { .func_arg = opt_target }, > "specify target file type (\"vcd\", \"svcd\", \"dvd\", \"dv\" > or \"dv50\" " > "with optional prefixes \"pal-\", \"ntsc-\" or \"film-\")", > "type" },
diff --git a/doc/ffmpeg.texi b/doc/ffmpeg.texi index d433d60ce9..a519fea192 100644 --- a/doc/ffmpeg.texi +++ b/doc/ffmpeg.texi @@ -1709,6 +1709,8 @@ it may cause packet loss. It is useful for when flow speed of output packets is important, such as live streaming. @item -re (@emph{input}) Read input at native frame rate. This is equivalent to setting @code{-readrate 1}. +@item -irb @var{seconds} +Set an initial read burst time, in seconds, after which any specified readrate will be enforced. @item -vsync @var{parameter} (@emph{global}) @itemx -fps_mode[:@var{stream_specifier}] @var{parameter} (@emph{output,per-stream}) Set video sync method / framerate mode. vsync is applied to all output video streams diff --git a/fftools/ffmpeg.h b/fftools/ffmpeg.h index 823218e214..e057e6da3a 100644 --- a/fftools/ffmpeg.h +++ b/fftools/ffmpeg.h @@ -124,6 +124,7 @@ typedef struct OptionsContext { int loop; int rate_emu; float readrate; + double initial_read_burst; int accurate_seek; int thread_queue_size; int input_sync_ref; @@ -475,6 +476,7 @@ typedef struct InputFile { int rate_emu; float readrate; + double initial_read_burst; int accurate_seek; /* when looping the input file, this queue is used by decoders to report diff --git a/fftools/ffmpeg_opt.c b/fftools/ffmpeg_opt.c index 055275d813..6c55b6cb01 100644 --- a/fftools/ffmpeg_opt.c +++ b/fftools/ffmpeg_opt.c @@ -1443,6 +1443,9 @@ const OptionDef options[] = { { "readrate", HAS_ARG | OPT_FLOAT | OPT_OFFSET | OPT_EXPERT | OPT_INPUT, { .off = OFFSET(readrate) }, "read input at specified rate", "speed" }, + { "irb", HAS_ARG | OPT_DOUBLE | OPT_OFFSET | + OPT_EXPERT | OPT_INPUT, { .off = OFFSET(initial_read_burst) }, + "The initial amount of input to burst read before imposing any readrate", "seconds" },
Implemented is the -irb <seconds> flag (i.e. "initial read burst") that causes ffmpeg to read the specified number of seconds of input before a given readrate starts to be enforced. All inputs have to reach this point before the readrate is enforced. The reason for this change is, in the scenario of live-streaming by transcoding from an pre-recorded or delayed source to an HLS or DASH webroot, we can more quickly prime the system of the first few seconds before the real-world read rate is imposed. Else, one must wait for an entire segment length before the data can be fetched from the web server. Signed-off-by: Davy Durham <ddurham@users.sourceforge.net> --- doc/ffmpeg.texi | 2 ++ fftools/ffmpeg.h | 2 ++ fftools/ffmpeg_opt.c | 3 +++ 3 files changed, 7 insertions(+) { "target", HAS_ARG | OPT_PERFILE | OPT_OUTPUT, { .func_arg = opt_target }, "specify target file type (\"vcd\", \"svcd\", \"dvd\", \"dv\" or \"dv50\" " "with optional prefixes \"pal-\", \"ntsc-\" or \"film-\")", "type" },