[FFmpeg-devel] [PATCH 1/2] lavf/segment: add support for specifying clock time offset

[Stefano Sabatini]

On date Monday 2016-01-18 21:56:29 +0100, Marton Balint encoded:
> Signed-off-by: Marton Balint <cus at passwd.hu>
> ---
>  doc/muxers.texi       | 10 ++++++++++
>  libavformat/segment.c | 11 ++++++++++-
>  2 files changed, 20 insertions(+), 1 deletion(-)
> 
> diff --git a/doc/muxers.texi b/doc/muxers.texi
> index a308d3d..c304221 100644
> --- a/doc/muxers.texi
> +++ b/doc/muxers.texi
> @@ -1100,6 +1100,16 @@ to create files at 12:00 o'clock, 12:15, 12:30, etc.
>  
>  Default value is "0".
>  
> + at item segment_clocktime_offset @var{duration}

> +By setting this option you can delay the segment splitting times with the
> +specified duration when using @option{segment_atclocktime}.
 
Nit:

Delay the segment splitting times with the specified duration when
using @option{segment_atclocktime}.
 
> +For example with @option{segment_time} set to "900" and
> + at option{segment_clocktime_offset} set to "300" this makes it possible to
> +create files at 12:05, 12:20, 12:35, etc.
> +
> +Default value is "0".
> +
>  @item segment_time_delta @var{delta}
>  Specify the accuracy time when selecting the start time for a
>  segment, expressed as a duration specification. Default value is "0".
> diff --git a/libavformat/segment.c b/libavformat/segment.c
> index 0c1f633..bf7a8fc 100644
> --- a/libavformat/segment.c
> +++ b/libavformat/segment.c
> @@ -82,6 +82,7 @@ typedef struct SegmentContext {
>      int   list_size;       ///< number of entries for the segment list file
>  
>      int use_clocktime;    ///< flag to cut segments at regular clock time
> +    int64_t clocktime_offset; //< clock offset for cutting the segments at regular clock time
>      int64_t last_val;      ///< remember last time for wrap around detection
>      int64_t last_cut;      ///< remember last cut
>      int cut_pending;
> @@ -633,6 +634,13 @@ static int seg_write_header(AVFormatContext *s)
>                     seg->time_str);
>              return ret;
>          }
> +        if (seg->use_clocktime) {

> +            if (seg->time <= 0) {
> +                av_log(s, AV_LOG_ERROR, "Invalid segment_time\n");

Nit: "Invalid negative segment_time with segment_atclocktime option set\n"

> +                return AVERROR(EINVAL);
> +            }
> +            seg->clocktime_offset = seg->time - (seg->clocktime_offset % seg->time);
> +        }
>      }
>  
>      if (seg->format_options_str) {
> @@ -775,7 +783,7 @@ static int seg_write_packet(AVFormatContext *s, AVPacket *pkt)
>              time_t sec = avgt / 1000000;
>              localtime_r(&sec, &ti);
>              usecs = (int64_t)(ti.tm_hour * 3600 + ti.tm_min * 60 + ti.tm_sec) * 1000000 + (avgt % 1000000);
> -            wrapped_val = usecs % seg->time;
> +            wrapped_val = (usecs + seg->clocktime_offset) % seg->time;
>              if (seg->last_cut != usecs && wrapped_val < seg->last_val) {
>                  seg->cut_pending = 1;
>                  seg->last_cut = usecs;
> @@ -926,6 +934,7 @@ static const AVOption options[] = {
>      { "hls", "Apple HTTP Live Streaming compatible", 0, AV_OPT_TYPE_CONST, {.i64=LIST_TYPE_M3U8 }, INT_MIN, INT_MAX, E, "list_type" },
>  
>      { "segment_atclocktime",      "set segment to be cut at clocktime",  OFFSET(use_clocktime), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, E},
> +    { "segment_clocktime_offset", "set segment clocktime offset",        OFFSET(clocktime_offset), AV_OPT_TYPE_DURATION, {.i64 = 0}, 0, 86400, E},

86400=> I think the maximum value must be expressed in microseconds

>      { "segment_time",      "set segment duration",                       OFFSET(time_str),AV_OPT_TYPE_STRING, {.str = NULL},  0, 0,       E },
>      { "segment_time_delta","set approximation value used for the segment times", OFFSET(time_delta), AV_OPT_TYPE_DURATION, {.i64 = 0}, 0, 0, E },
>      { "segment_times",     "set segment split time points",              OFFSET(times_str),AV_OPT_TYPE_STRING,{.str = NULL},  0, 0,       E },

[...]
-- 
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