[FFmpeg-soc] [soc]: r5227 - concat/libavformat/concatgen.c

[gkovacs]

Author: gkovacs
Date: Mon Aug 24 04:39:15 2009
New Revision: 5227

Log:
use static variable to cache result of av_playlist_time_offset to reduce computations in read_packet

Modified:
   concat/libavformat/concatgen.c

Modified: concat/libavformat/concatgen.c
==============================================================================
--- concat/libavformat/concatgen.c	Mon Aug 24 04:20:33 2009	(r5226)
+++ concat/libavformat/concatgen.c	Mon Aug 24 04:39:15 2009	(r5227)
@@ -52,14 +52,21 @@ int ff_concatgen_read_packet(AVFormatCon
         }
         if (ret >= 0) {
             if (pkt) {
+                int streams_offset = av_playlist_streams_offset_from_playidx(ctx, ctx->pe_curidx);
                 stream_index = av_playlist_localstidx_from_streamidx(ctx, pkt->stream_index);
-                pkt->stream_index = stream_index + av_playlist_streams_offset_from_playidx(ctx, ctx->pe_curidx);
+                pkt->stream_index = stream_index + streams_offset;
                 if (!ic->streams[stream_index]->codec->has_b_frames ||
                     ic->streams[stream_index]->codec->codec->id == CODEC_ID_MPEG1VIDEO) {
-                    int time_offset_avbase = av_playlist_time_offset(ctx->durations, ctx->pe_curidx);
-                    int time_offset_localbase = av_rescale_q(time_offset_avbase,
-                                                             AV_TIME_BASE_Q,
-                                                             ic->streams[stream_index]->time_base);
+                    static int cached_streams_offset = -1;
+                    static int64_t time_offset_avbase = 0;
+                    int time_offset_localbase;
+                    if (cached_streams_offset != streams_offset) { // must recompute timestamp offset
+                        cached_streams_offset = streams_offset;
+                        time_offset_avbase = av_playlist_time_offset(ctx->durations, streams_offset);
+                    }
+                    time_offset_localbase = av_rescale_q(time_offset_avbase,
+                                                         AV_TIME_BASE_Q,
+                                                         ic->streams[stream_index]->time_base);
                     pkt->dts += time_offset_localbase;
                     if (pkt->pts != AV_NOPTS_VALUE)
                         pkt->pts += time_offset_localbase;