[FFmpeg-devel] [PATCH 3/4] concatdec: add support for specifying outpoint of files

[Marton Balint]

Signed-off-by: Marton Balint <cus at passwd.hu>
---
 doc/demuxers.texi       | 13 +++++++++++++
 libavformat/concatdec.c | 22 ++++++++++++++++++++--
 2 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/doc/demuxers.texi b/doc/demuxers.texi
index 4bad1c8..4ba797e 100644
--- a/doc/demuxers.texi
+++ b/doc/demuxers.texi
@@ -129,6 +129,19 @@ directive) will be reduced based on their specified In point.
 Because of potential packets before the specified In point, packet timestamps
 may overlap between two concatenated files.
 
+ at item @code{out @var{timestamp}}
+Out point of the file. When the demuxer reaches the specified timestamp in any
+of the streams, it handles it as an end of file condition. Out point is
+exclusive, which means that the demuxer will not output packets which has a
+timestamp greater or equal to Out point.
+
+This directive works best with intra frame codecs, because for non-intra frame
+ones you will usually not get enough packets to decode the last few frames
+before the specified Out point.
+
+The duration of the files (if not specified by the @code{duration}
+directive) will be reduced based on their specified Out point.
+
 @item @code{stream}
 Introduce a stream in the virtual file.
 All subsequent stream-related directives apply to the last introduced
diff --git a/libavformat/concatdec.c b/libavformat/concatdec.c
index 11e6759..eaf34b0 100644
--- a/libavformat/concatdec.c
+++ b/libavformat/concatdec.c
@@ -44,6 +44,7 @@ typedef struct {
     int64_t duration;
     ConcatStream *streams;
     int64_t inpoint;
+    int64_t outpoint;
     int nb_streams;
 } ConcatFile;
 
@@ -145,6 +146,7 @@ static int add_file(AVFormatContext *avf, char *filename, ConcatFile **rfile,
     file->start_time = AV_NOPTS_VALUE;
     file->duration   = AV_NOPTS_VALUE;
     file->inpoint    = AV_NOPTS_VALUE;
+    file->outpoint   = AV_NOPTS_VALUE;
 
     return 0;
 
@@ -360,7 +362,7 @@ static int concat_read_header(AVFormatContext *avf)
             }
             if ((ret = add_file(avf, filename, &file, &nb_files_alloc)) < 0)
                 goto fail;
-        } else if (!strcmp(keyword, "duration") || !strcmp(keyword, "in")) {
+        } else if (!strcmp(keyword, "duration") || !strcmp(keyword, "in") || !strcmp(keyword, "out")) {
             char *dur_str = get_keyword(&cursor);
             int64_t dur;
             if (!file) {
@@ -377,6 +379,8 @@ static int concat_read_header(AVFormatContext *avf)
                 file->duration = dur;
             else if (!strcmp(keyword, "in"))
                 file->inpoint = dur;
+            else if (!strcmp(keyword, "out"))
+                file->outpoint = dur;
         } else if (!strcmp(keyword, "stream")) {
             if (!avformat_new_stream(avf, NULL))
                 FAIL(AVERROR(ENOMEM));
@@ -443,6 +447,8 @@ static int open_next_file(AVFormatContext *avf)
         cat->cur_file->duration = cat->avf->duration;
         if (cat->cur_file->inpoint != AV_NOPTS_VALUE)
             cat->cur_file->duration -= (cat->cur_file->inpoint - file_start_time);
+        if (cat->cur_file->outpoint != AV_NOPTS_VALUE)
+            cat->cur_file->duration -= cat->avf->duration - (cat->cur_file->outpoint - file_start_time);
     }
 
     if (++fileno >= cat->nb_files) {
@@ -504,6 +510,16 @@ static int64_t get_cur_file_inpoint(ConcatContext *cat)
     return file_inpoint;
 }
 
+/* Returns true if the packet pts is greater or equal to the specified outpoint. */
+static int packet_after_outpoint(ConcatContext *cat, AVPacket *pkt)
+{
+    if (cat->cur_file->outpoint != AV_NOPTS_VALUE && pkt->pts != AV_NOPTS_VALUE) {
+        return av_compare_ts(pkt->pts, cat->avf->streams[pkt->stream_index]->time_base,
+                             cat->cur_file->outpoint, AV_TIME_BASE_Q) >= 0;
+    }
+    return 0;
+}
+
 static int concat_read_packet(AVFormatContext *avf, AVPacket *pkt)
 {
     ConcatContext *cat = avf->priv_data;
@@ -520,7 +536,9 @@ static int concat_read_packet(AVFormatContext *avf, AVPacket *pkt)
 
     while (1) {
         ret = av_read_frame(cat->avf, pkt);
-        if (ret == AVERROR_EOF) {
+        if (ret == AVERROR_EOF || packet_after_outpoint(cat, pkt)) {
+            if (ret == 0)
+                av_packet_unref(pkt);
             if ((ret = open_next_file(avf)) < 0)
                 return ret;
             continue;
-- 
2.1.4