Merge commit '398f015f'

* commit '398f015f':
  avconv: buffer the packets written while the muxer is not initialized
Merged-by: Hendrik Leppkes <h.leppkes@gmail.com>

doc/ffmpeg.texi

@@ -1279,6 +1279,15 @@ No packets were passed to the muxer, the output is empty.
 @item -xerror (@emph{global})
 Stop and exit on error
 
+@item -max_muxing_queue_size @var{packets} (@emph{output,per-stream})
+When transcoding audio and/or video streams, ffmpeg will not begin writing into
+the output until it has one packet for each such stream. While waiting for that
+to happen, packets for other streams are buffered. This option sets the size of
+this buffer, in packets, for the matching output stream.
+
+The default value of this option should be high enough for most uses, so only
+touch this option if you are sure that you need it.
+
 @end table
 
 As a special exception, you can use a bitmap subtitle stream as input: it

ffmpeg.c

@@ -533,6 +533,13 @@ static void ffmpeg_cleanup(int ret)
         avcodec_free_context(&ost->enc_ctx);
         avcodec_parameters_free(&ost->ref_par);
 
+        while (av_fifo_size(ost->muxing_queue)) {
+            AVPacket pkt;
+            av_fifo_generic_read(ost->muxing_queue, &pkt, sizeof(pkt), NULL);
+            av_packet_unref(&pkt);
+        }
+        av_fifo_free(ost->muxing_queue);
+
         av_freep(&output_streams[i]);
     }
 #if HAVE_PTHREADS
@@ -635,11 +642,33 @@ static void close_all_output_streams(OutputStream *ost, OSTFinished this_stream,
     }
 }
 
-static void write_packet(AVFormatContext *s, AVPacket *pkt, OutputStream *ost)
+static void write_packet(OutputFile *of, AVPacket *pkt, OutputStream *ost)
 {
+    AVFormatContext *s = of->ctx;
     AVStream *st = ost->st;
     int ret;
 
+    if (!of->header_written) {
+        AVPacket tmp_pkt;
+        /* the muxer is not initialized yet, buffer the packet */
+        if (!av_fifo_space(ost->muxing_queue)) {
+            int new_size = FFMIN(2 * av_fifo_size(ost->muxing_queue),
+                                 ost->max_muxing_queue_size);
+            if (new_size <= av_fifo_size(ost->muxing_queue)) {
+                av_log(NULL, AV_LOG_ERROR,
+                       "Too many packets buffered for output stream %d:%d.\n",
+                       ost->file_index, ost->st->index);
+                exit_program(1);
+            }
+            ret = av_fifo_realloc2(ost->muxing_queue, new_size);
+            if (ret < 0)
+                exit_program(1);
+        }
+        av_packet_move_ref(&tmp_pkt, pkt);
+        av_fifo_generic_write(ost->muxing_queue, &tmp_pkt, sizeof(tmp_pkt), NULL);
+        return;
+    }
+
     if ((st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO && video_sync_method == VSYNC_DROP) ||
         (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO && audio_sync_method < 0))
         pkt->pts = pkt->dts = AV_NOPTS_VALUE;
@@ -752,7 +781,7 @@ static void close_output_stream(OutputStream *ost)
     }
 }
 
-static void output_packet(AVFormatContext *s, AVPacket *pkt, OutputStream *ost)
+static void output_packet(OutputFile *of, AVPacket *pkt, OutputStream *ost)
 {
     int ret = 0;
 
@@ -800,10 +829,10 @@ static void output_packet(AVFormatContext *s, AVPacket *pkt, OutputStream *ost)
                     goto finish;
                 idx++;
             } else
-                write_packet(s, pkt, ost);
+                write_packet(of, pkt, ost);
         }
     } else
-        write_packet(s, pkt, ost);
+        write_packet(of, pkt, ost);
 
 finish:
     if (ret < 0 && ret != AVERROR_EOF) {
@@ -827,7 +856,7 @@ static int check_recording_time(OutputStream *ost)
     return 1;
 }
 
-static void do_audio_out(AVFormatContext *s, OutputStream *ost,
+static void do_audio_out(OutputFile *of, OutputStream *ost,
                          AVFrame *frame)
 {
     AVCodecContext *enc = ost->enc_ctx;
@@ -878,7 +907,7 @@ static void do_audio_out(AVFormatContext *s, OutputStream *ost,
                    av_ts2str(pkt.dts), av_ts2timestr(pkt.dts, &ost->st->time_base));
         }
 
-        output_packet(s, &pkt, ost);
+        output_packet(of, &pkt, ost);
     }
 
     return;
@@ -887,7 +916,7 @@ error:
     exit_program(1);
 }
 
-static void do_subtitle_out(AVFormatContext *s,
+static void do_subtitle_out(OutputFile *of,
                             OutputStream *ost,
                             InputStream *ist,
                             AVSubtitle *sub)
@@ -967,11 +996,11 @@ static void do_subtitle_out(AVFormatContext *s,
                 pkt.pts += 90 * sub->end_display_time;
         }
         pkt.dts = pkt.pts;
-        output_packet(s, &pkt, ost);
+        output_packet(of, &pkt, ost);
     }
 }
 
-static void do_video_out(AVFormatContext *s,
+static void do_video_out(OutputFile *of,
                          OutputStream *ost,
                          AVFrame *next_picture,
                          double sync_ipts)
@@ -1020,10 +1049,10 @@ static void do_video_out(AVFormatContext *s,
 
         format_video_sync = video_sync_method;
         if (format_video_sync == VSYNC_AUTO) {
-            if(!strcmp(s->oformat->name, "avi")) {
+            if(!strcmp(of->ctx->oformat->name, "avi")) {
                 format_video_sync = VSYNC_VFR;
             } else
-                format_video_sync = (s->oformat->flags & AVFMT_VARIABLE_FPS) ? ((s->oformat->flags & AVFMT_NOTIMESTAMPS) ? VSYNC_PASSTHROUGH : VSYNC_VFR) : VSYNC_CFR;
+                format_video_sync = (of->ctx->oformat->flags & AVFMT_VARIABLE_FPS) ? ((of->ctx->oformat->flags & AVFMT_NOTIMESTAMPS) ? VSYNC_PASSTHROUGH : VSYNC_VFR) : VSYNC_CFR;
             if (   ist
                 && format_video_sync == VSYNC_CFR
                 && input_files[ist->file_index]->ctx->nb_streams == 1
@@ -1134,7 +1163,7 @@ static void do_video_out(AVFormatContext *s,
         return;
 
 #if FF_API_LAVF_FMT_RAWPICTURE
-    if (s->oformat->flags & AVFMT_RAWPICTURE &&
+    if (of->ctx->oformat->flags & AVFMT_RAWPICTURE &&
         enc->codec->id == AV_CODEC_ID_RAWVIDEO) {
         /* raw pictures are written as AVPicture structure to
            avoid any copies. We support temporarily the older
@@ -1148,7 +1177,7 @@ static void do_video_out(AVFormatContext *s,
         pkt.pts    = av_rescale_q(in_picture->pts, enc->time_base, ost->st->time_base);
         pkt.flags |= AV_PKT_FLAG_KEY;
 
-        output_packet(s, &pkt, ost);
+        output_packet(of, &pkt, ost);
     } else
 #endif
     {
@@ -1251,7 +1280,7 @@ static void do_video_out(AVFormatContext *s,
             }
 
             frame_size = pkt.size;
-            output_packet(s, &pkt, ost);
+            output_packet(of, &pkt, ost);
 
             /* if two pass, output log */
             if (ost->logfile && enc->stats_out) {
@@ -1379,7 +1408,7 @@ static int reap_filters(int flush)
                            "Error in av_buffersink_get_frame_flags(): %s\n", av_err2str(ret));
                 } else if (flush && ret == AVERROR_EOF) {
                     if (filter->inputs[0]->type == AVMEDIA_TYPE_VIDEO)
-                        do_video_out(of->ctx, ost, NULL, AV_NOPTS_VALUE);
+                        do_video_out(of, ost, NULL, AV_NOPTS_VALUE);
                 }
                 break;
             }
@@ -1419,7 +1448,7 @@ static int reap_filters(int flush)
                             enc->time_base.num, enc->time_base.den);
                 }
 
-                do_video_out(of->ctx, ost, filtered_frame, float_pts);
+                do_video_out(of, ost, filtered_frame, float_pts);
                 break;
             case AVMEDIA_TYPE_AUDIO:
                 if (!(enc->codec->capabilities & AV_CODEC_CAP_PARAM_CHANGE) &&
@@ -1428,7 +1457,7 @@ static int reap_filters(int flush)
                            "Audio filter graph output is not normalized and encoder does not support parameter changes\n");
                     break;
                 }
-                do_audio_out(of->ctx, ost, filtered_frame);
+                do_audio_out(of, ost, filtered_frame);
                 break;
             default:
                 // TODO support subtitle filters
@@ -1758,7 +1787,7 @@ static void flush_encoders(void)
     for (i = 0; i < nb_output_streams; i++) {
         OutputStream   *ost = output_streams[i];
         AVCodecContext *enc = ost->enc_ctx;
-        AVFormatContext *os = output_files[ost->file_index]->ctx;
+        OutputFile      *of = output_files[ost->file_index];
         int stop_encoding = 0;
 
         if (!ost->encoding_needed)
@@ -1767,7 +1796,7 @@ static void flush_encoders(void)
         if (enc->codec_type == AVMEDIA_TYPE_AUDIO && enc->frame_size <= 1)
             continue;
 #if FF_API_LAVF_FMT_RAWPICTURE
-        if (enc->codec_type == AVMEDIA_TYPE_VIDEO && (os->oformat->flags & AVFMT_RAWPICTURE) && enc->codec->id == AV_CODEC_ID_RAWVIDEO)
+        if (enc->codec_type == AVMEDIA_TYPE_VIDEO && (of->ctx->oformat->flags & AVFMT_RAWPICTURE) && enc->codec->id == AV_CODEC_ID_RAWVIDEO)
             continue;
 #endif
 
@@ -1819,7 +1848,7 @@ static void flush_encoders(void)
                 }
                 av_packet_rescale_ts(&pkt, enc->time_base, ost->st->time_base);
                 pkt_size = pkt.size;
-                output_packet(os, &pkt, ost);
+                output_packet(of, &pkt, ost);
                 if (ost->enc_ctx->codec_type == AVMEDIA_TYPE_VIDEO && vstats_filename) {
                     do_video_stats(ost, pkt_size);
                 }
@@ -1961,7 +1990,7 @@ static void do_streamcopy(InputStream *ist, OutputStream *ost, const AVPacket *p
     }
 #endif
 
-    output_packet(of->ctx, &opkt, ost);
+    output_packet(of, &opkt, ost);
 }
 
 int guess_input_channel_layout(InputStream *ist)
@@ -2367,7 +2396,7 @@ static int transcode_subtitles(InputStream *ist, AVPacket *pkt, int *got_output)
             || ost->enc->type != AVMEDIA_TYPE_SUBTITLE)
             continue;
 
-        do_subtitle_out(output_files[ost->file_index]->ctx, ost, ist, &subtitle);
+        do_subtitle_out(output_files[ost->file_index], ost, ist, &subtitle);
     }
 
 out:
@@ -2756,6 +2785,17 @@ static int check_init_output_file(OutputFile *of, int file_index)
     if (sdp_filename || want_sdp)
         print_sdp();
 
+    /* flush the muxing queues */
+    for (i = 0; i < of->ctx->nb_streams; i++) {
+        OutputStream *ost = output_streams[of->ost_index + i];
+
+        while (av_fifo_size(ost->muxing_queue)) {
+            AVPacket pkt;
+            av_fifo_generic_read(ost->muxing_queue, &pkt, sizeof(pkt), NULL);
+            write_packet(of, &pkt, ost);
+        }
+    }
+
     return 0;
 }
 

ffmpeg.h

@@ -212,6 +212,8 @@ typedef struct OptionsContext {
     int        nb_pass;
     SpecifierOpt *passlogfiles;
     int        nb_passlogfiles;
+    SpecifierOpt *max_muxing_queue_size;
+    int        nb_max_muxing_queue_size;
     SpecifierOpt *guess_layout_max;
     int        nb_guess_layout_max;
     SpecifierOpt *apad;
@@ -499,6 +501,11 @@ typedef struct OutputStream {
     /* packet quality factor */
     int quality;
 
+    int max_muxing_queue_size;
+
+    /* the packets are buffered here until the muxer is ready to be initialized */
+    AVFifoBuffer *muxing_queue;
+
     /* packet picture type */
     int pict_type;
 

ffmpeg_opt.c

@@ -1395,6 +1395,10 @@ static OutputStream *new_output_stream(OptionsContext *o, AVFormatContext *oc, e
     MATCH_PER_STREAM_OPT(disposition, str, ost->disposition, oc, st);
     ost->disposition = av_strdup(ost->disposition);
 
+    ost->max_muxing_queue_size = 128;
+    MATCH_PER_STREAM_OPT(max_muxing_queue_size, i, ost->max_muxing_queue_size, oc, st);
+    ost->max_muxing_queue_size *= sizeof(AVPacket);
+
     if (oc->oformat->flags & AVFMT_GLOBALHEADER)
         ost->enc_ctx->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;
 
@@ -1414,6 +1418,10 @@ static OutputStream *new_output_stream(OptionsContext *o, AVFormatContext *oc, e
     }
     ost->last_mux_dts = AV_NOPTS_VALUE;
 
+    ost->muxing_queue = av_fifo_alloc(8 * sizeof(AVPacket));
+    if (!ost->muxing_queue)
+        exit_program(1);
+
     return ost;
 }
 
@@ -3565,6 +3573,10 @@ const OptionDef options[] = {
         "set the subtitle options to the indicated preset", "preset" },
     { "fpre", HAS_ARG | OPT_EXPERT| OPT_PERFILE | OPT_OUTPUT,                { .func_arg = opt_preset },
         "set options from indicated preset file", "filename" },
+
+    { "max_muxing_queue_size", HAS_ARG | OPT_INT | OPT_SPEC | OPT_EXPERT | OPT_OUTPUT, { .off = OFFSET(max_muxing_queue_size) },
+        "maximum number of packets that can be buffered while waiting for all streams to initialize", "packets" },
+
     /* data codec support */
     { "dcodec", HAS_ARG | OPT_DATA | OPT_PERFILE | OPT_EXPERT | OPT_INPUT | OPT_OUTPUT, { .func_arg = opt_data_codec },
         "force data codec ('copy' to copy stream)", "codec" },