[FFmpeg-devel] [PATCH] lavf/segment: add -segment_times option

Stefano Sabatini stefasab at gmail.com
Wed Jul 4 01:21:58 CEST 2012


This option allows to specify the split times for the resulting segments.

FIXME: bump micro
---
 doc/muxers.texi       |   11 +++++++
 libavformat/segment.c |   76 +++++++++++++++++++++++++++++++++++++++++++++----
 2 files changed, 81 insertions(+), 6 deletions(-)

diff --git a/doc/muxers.texi b/doc/muxers.texi
index 7531a52..c63356a 100644
--- a/doc/muxers.texi
+++ b/doc/muxers.texi
@@ -463,6 +463,10 @@ listfile is generated.
 @item segment_list_size @var{size}
 Overwrite the listfile once it reaches @var{size} entries. If 0
 the listfile is never overwritten. Default value is 5.
+ at item segment_times @var{times}
+Specify a list of split points. @var{times} contains a list of comma
+separated duration specifications, which are supposed to be in
+increasing order.
 @item segment_wrap @var{limit}
 Wrap around segment index once it reaches @var{limit}.
 @end table
@@ -479,6 +483,13 @@ ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.list out%03d.nu
 @end example
 
 @item
+As the example above, but segment the input file according to the split
+points specified by the @var{segment_times} option:
+ at example
+ffmpeg -i in.mkv -codec copy -map 0 -f segment -segment_list out.list -segment_times 10,20,40,50,90,120,180 out%03d.nut
+ at end example
+
+ at item
 To convert the @file{in.mkv} to TS segments using the @code{libx264}
 and @code{libfaac} encoders:
 @example
diff --git a/libavformat/segment.c b/libavformat/segment.c
index 429ca1e..54b9f9a 100644
--- a/libavformat/segment.c
+++ b/libavformat/segment.c
@@ -41,6 +41,9 @@ typedef struct {
     int  wrap;             ///< number after which the index wraps
     char *time_str;        ///< segment duration specification string
     int64_t time;          ///< segment duration
+    char *times_str;       ///< segment times specification string
+    int64_t *times;        ///< list of segment interval specification
+    int nb_times;          ///< number of elments in the times array
     int has_video;
     double start_time, end_time;
 } SegmentContext;
@@ -124,6 +127,45 @@ end:
     return ret;
 }
 
+static int parse_times(void *log_ctx, int64_t **times, int *nb_times,
+                       const char *times_str)
+{
+    const char *p;
+    int i, ret;
+    *nb_times = 1;
+
+    for (p = times_str; *p; p++)
+        if (*p == ',')
+            (*nb_times)++;
+
+    *times = av_realloc_f(NULL, sizeof(**times), *nb_times);
+    if (!*times) {
+        av_log(log_ctx, AV_LOG_ERROR, "Could not allocate forced times array.\n");
+        return AVERROR(ENOMEM);
+    }
+
+    for (i = 0; i < *nb_times; i++) {
+        int64_t t;
+        p = i ? strchr(p, ',') + 1 : times_str;
+        ret = av_parse_time(&t, p, 1);
+        if (ret < 0) {
+            av_log(log_ctx, AV_LOG_ERROR,
+                   "Invalid time duration specification in %s.\n", p);
+            return AVERROR(EINVAL);
+        }
+        (*times)[i] = t;
+
+        /* check on monotonicity */
+        if (i && (*times)[i-1] > (*times)[i]) {
+            av_log(log_ctx, AV_LOG_ERROR,
+                   "Specified time %f is greater than the following time %f\n",
+                   (float)((*times)[i])/1000000, (float)((*times)[i-1])/1000000);
+            return AVERROR(EINVAL);
+        }
+    }
+    return 0;
+}
+
 static int seg_write_header(AVFormatContext *s)
 {
     SegmentContext *seg = s->priv_data;
@@ -132,11 +174,25 @@ static int seg_write_header(AVFormatContext *s)
 
     seg->number = 0;
 
-    if ((ret = av_parse_time(&seg->time, seg->time_str, 1)) < 0) {
+    if (seg->time_str && seg->times_str) {
         av_log(s, AV_LOG_ERROR,
-               "Invalid time duration specification '%s' for segment_time option\n",
-               seg->time_str);
-        return ret;
+               "segment_time and segment_times options are mutually exclusive, select just one of them\n");
+        return AVERROR(EINVAL);
+    }
+
+    if (seg->times_str) {
+        if ((ret = parse_times(s, &seg->times, &seg->nb_times, seg->times_str)) < 0)
+            return ret;
+    } else {
+        /* set default value if not specified */
+        if (!seg->time_str)
+            seg->time_str = av_strdup("2");
+        if ((ret = av_parse_time(&seg->time, seg->time_str, 1)) < 0) {
+            av_log(s, AV_LOG_ERROR,
+                   "Invalid time duration specification '%s' for segment_time option\n",
+                   seg->time_str);
+            return ret;
+        }
     }
 
     oc = avformat_alloc_context();
@@ -209,9 +265,15 @@ static int seg_write_packet(AVFormatContext *s, AVPacket *pkt)
     SegmentContext *seg = s->priv_data;
     AVFormatContext *oc = seg->avf;
     AVStream *st = oc->streams[pkt->stream_index];
-    int64_t end_pts = seg->time * seg->number;
+    int64_t end_pts;
     int ret;
 
+    if (seg->times) {
+        end_pts = seg->number <= seg->nb_times ? seg->times[seg->number-1] : INT64_MAX;
+    } else {
+        end_pts = seg->time * seg->number;
+    }
+
     /* if the segment has video, start a new segment *only* with a key video frame */
     if ((st->codec->codec_type == AVMEDIA_TYPE_VIDEO || !seg->has_video) &&
         av_compare_ts(pkt->pts, st->time_base,
@@ -252,6 +314,7 @@ static int seg_write_trailer(struct AVFormatContext *s)
         avio_close(seg->list_pb);
 
     av_opt_free(seg);
+    av_freep(&seg->times);
 
     oc->streams = NULL;
     oc->nb_streams = 0;
@@ -263,7 +326,8 @@ static int seg_write_trailer(struct AVFormatContext *s)
 #define E AV_OPT_FLAG_ENCODING_PARAM
 static const AVOption options[] = {
     { "segment_format",    "set container format used for the segments", OFFSET(format),  AV_OPT_TYPE_STRING, {.str = NULL},  0, 0,       E },
-    { "segment_time",      "set segment duration",                       OFFSET(time_str), AV_OPT_TYPE_STRING,{.str = "2"},  0, 0,      E },
+    { "segment_time",      "set segment duration",                       OFFSET(time_str), AV_OPT_TYPE_STRING,{.str = NULL},  0, 0,       E },
+    { "segment_times",     "set segment split time points",              OFFSET(times_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0,      E },
     { "segment_list",      "set the segment list filename",              OFFSET(list),    AV_OPT_TYPE_STRING, {.str = NULL},  0, 0,       E },
     { "segment_list_size", "set the maximum number of playlist entries", OFFSET(list_size), AV_OPT_TYPE_INT,  {.dbl = 5},     0, INT_MAX, E },
     { "segment_wrap",      "set number after which the index wraps",     OFFSET(wrap),    AV_OPT_TYPE_INT,    {.dbl = 0},     0, INT_MAX, E },
-- 
1.7.5.4



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