avformat/flvenc: add no_sequence_end flags for flvflags

when split flv file by flv format at first, and cat flvs file
into one flv file, the flv sequence end is be used,
then the whole flv have many flv sequence end TAG.
this flags can give user an option to ignore write sequence end TAG

Signed-off-by: Steven Liu <lingjiujianke@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libavformat/flvenc.c

@@ -63,6 +63,7 @@ static const AVCodecTag flv_audio_codec_ids[] = {
 
 typedef enum {
     FLV_AAC_SEQ_HEADER_DETECT = (1 << 0),
+    FLV_NO_SEQUENCE_END = (1 << 1),
 } FLVFlags;
 
 typedef struct FLVContext {
@@ -527,6 +528,9 @@ static int flv_write_trailer(AVFormatContext *s)
     FLVContext *flv = s->priv_data;
     int i;
 
+    if (flv->flags & FLV_NO_SEQUENCE_END) {
+        av_log(s, AV_LOG_DEBUG, "FLV no sequence end mode open\n");
+    } else {
         /* Add EOS tag */
         for (i = 0; i < s->nb_streams; i++) {
             AVCodecParameters *par = s->streams[i]->codecpar;
@@ -535,6 +539,7 @@ static int flv_write_trailer(AVFormatContext *s)
                     (par->codec_id == AV_CODEC_ID_H264 || par->codec_id == AV_CODEC_ID_MPEG4))
                 put_avc_eos_tag(pb, sc->last_ts);
         }
+    }
 
     file_size = avio_tell(pb);
 
@@ -723,6 +728,7 @@ static int flv_write_packet(AVFormatContext *s, AVPacket *pkt)
 static const AVOption options[] = {
     { "flvflags", "FLV muxer flags", offsetof(FLVContext, flags), AV_OPT_TYPE_FLAGS, {.i64 = 0}, INT_MIN, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM, "flvflags" },
     { "aac_seq_header_detect", "Put AAC sequence header based on stream data", 0, AV_OPT_TYPE_CONST, {.i64 = FLV_AAC_SEQ_HEADER_DETECT}, INT_MIN, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM, "flvflags" },
+    { "no_sequence_end", "disable sequence end for FLV", 0, AV_OPT_TYPE_CONST, {.i64 = FLV_NO_SEQUENCE_END}, INT_MIN, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM, "flvflags" },
     { NULL },
 };