Add -t option to ffplay.

Patch by Robert Krüger, krueger signal7 de

Originally committed as revision 22764 to svn://svn.ffmpeg.org/ffmpeg/trunk

doc/ffplay-doc.texi

@@ -45,6 +45,8 @@ Disable audio.
 Disable video.
 @item -ss @var{pos}
 Seek to a given position in seconds.
+@item -t @var{duration}
+play <duration> seconds of audio/video
 @item -bytes
 Seek by bytes.
 @item -nodisp

ffplay.c

@@ -244,6 +244,7 @@ static int display_disable;
 static int show_status = 1;
 static int av_sync_type = AV_SYNC_AUDIO_MASTER;
 static int64_t start_time = AV_NOPTS_VALUE;
+static int64_t duration = AV_NOPTS_VALUE;
 static int debug = 0;
 static int debug_mv = 0;
 static int step = 0;
@@ -2360,6 +2361,7 @@ static int decode_thread(void *arg)
     AVPacket pkt1, *pkt = &pkt1;
     AVFormatParameters params, *ap = &params;
     int eof=0;
+    int pkt_in_play_range = 0;
 
     ic = avformat_alloc_context();
 
@@ -2559,11 +2561,17 @@ static int decode_thread(void *arg)
             SDL_Delay(100); /* wait for user event */
             continue;
         }
-        if (pkt->stream_index == is->audio_stream) {
+        /* check if packet is in play range specified by user, then queue, otherwise discard */
+        pkt_in_play_range = duration == AV_NOPTS_VALUE ||
+                (pkt->pts - ic->streams[pkt->stream_index]->start_time) *
+                av_q2d(ic->streams[pkt->stream_index]->time_base) -
+                (double)(start_time != AV_NOPTS_VALUE ? start_time : 0)/1000000
+                <= ((double)duration/1000000);
+        if (pkt->stream_index == is->audio_stream && pkt_in_play_range) {
             packet_queue_put(&is->audioq, pkt);
-        } else if (pkt->stream_index == is->video_stream) {
+        } else if (pkt->stream_index == is->video_stream && pkt_in_play_range) {
             packet_queue_put(&is->videoq, pkt);
-        } else if (pkt->stream_index == is->subtitle_stream) {
+        } else if (pkt->stream_index == is->subtitle_stream && pkt_in_play_range) {
             packet_queue_put(&is->subtitleq, pkt);
         } else {
             av_free_packet(pkt);
@@ -2971,6 +2979,12 @@ static int opt_seek(const char *opt, const char *arg)
     return 0;
 }
 
+static int opt_duration(const char *opt, const char *arg)
+{
+    duration = parse_time_or_die(opt, arg, 1);
+    return 0;
+}
+
 static int opt_debug(const char *opt, const char *arg)
 {
     av_log_set_level(99);
@@ -3005,6 +3019,7 @@ static const OptionDef options[] = {
     { "vst", OPT_INT | HAS_ARG | OPT_EXPERT, {(void*)&wanted_stream[AVMEDIA_TYPE_VIDEO]}, "select desired video stream", "stream_number" },
     { "sst", OPT_INT | HAS_ARG | OPT_EXPERT, {(void*)&wanted_stream[AVMEDIA_TYPE_SUBTITLE]}, "select desired subtitle stream", "stream_number" },
     { "ss", HAS_ARG | OPT_FUNC2, {(void*)&opt_seek}, "seek to a given position in seconds", "pos" },
+    { "t", HAS_ARG | OPT_FUNC2, {(void*)&opt_duration}, "play  \"duration\" seconds of audio/video", "duration" },
     { "bytes", OPT_INT | HAS_ARG, {(void*)&seek_by_bytes}, "seek by bytes 0=off 1=on -1=auto", "val" },
     { "nodisp", OPT_BOOL, {(void*)&display_disable}, "disable graphical display" },
     { "f", HAS_ARG, {(void*)opt_format}, "force format", "fmt" },