SCR timestamp fix try #1

Originally committed as revision 3550 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/avformat.h

@@ -524,6 +524,7 @@ void fifo_free(FifoBuffer *f);
 int fifo_size(FifoBuffer *f, uint8_t *rptr);
 int fifo_read(FifoBuffer *f, uint8_t *buf, int buf_size, uint8_t **rptr_ptr);
 void fifo_write(FifoBuffer *f, uint8_t *buf, int size, uint8_t **wptr_ptr);
+int put_fifo(ByteIOContext *pb, FifoBuffer *f, int buf_size, uint8_t **rptr_ptr);
 
 /* media file input */
 AVInputFormat *av_find_input_format(const char *short_name);

libavformat/mpeg.c

@@ -19,18 +19,29 @@
 #include "avformat.h"
 
 #define MAX_PAYLOAD_SIZE 4096
+#define PRELOAD 45000 //0.5sec
 //#define DEBUG_SEEK
 
 #undef NDEBUG
 #include <assert.h>
 
+typedef struct PacketDesc {
+    int64_t pts;
+    int64_t dts;
+    int size;
+    int unwritten_size;
+    int flags;
+    struct PacketDesc *next;
+} PacketDesc;
+
 typedef struct {
-    uint8_t buffer[MAX_PAYLOAD_SIZE];
-    int buffer_ptr;
-    int nb_frames;    /* number of starting frame encountered (AC3) */
-    int frame_start_offset; /* starting offset of the frame + 1 (0 if none) */
+    FifoBuffer fifo;
     uint8_t id;
     int max_buffer_size; /* in bytes */
+    int buffer_index;
+    PacketDesc *predecode_packet;
+    PacketDesc *premux_packet;
+    PacketDesc **next_packet;
     int packet_number;
     int64_t start_pts;
     int64_t start_dts;
@@ -51,8 +62,6 @@ typedef struct {
     int is_mpeg2;
     int is_vcd;
     int is_svcd;
-    int scr_stream_index; /* stream from which the system clock is
-                             computed (VBR case) */
     int64_t last_scr; /* current system clock */
 
     double vcd_padding_bitrate; //FIXME floats
@@ -127,7 +136,7 @@ static int put_pack_header(AVFormatContext *ctx,
 static int put_system_header(AVFormatContext *ctx, uint8_t *buf,int only_for_stream_id)
 {
     MpegMuxContext *s = ctx->priv_data;
-    int size, rate_bound, i, private_stream_coded, id;
+    int size, i, private_stream_coded, id;
     PutBitContext pb;
 
     init_put_bits(&pb, buf, 128);
@@ -136,8 +145,7 @@ static int put_system_header(AVFormatContext *ctx, uint8_t *buf,int only_for_str
     put_bits(&pb, 16, 0);
     put_bits(&pb, 1, 1);
     
-    rate_bound = s->mux_rate; /* maximum bit rate of the multiplexed stream */
-    put_bits(&pb, 22, rate_bound);
+    put_bits(&pb, 22, s->mux_rate); /* maximum bit rate of the multiplexed stream */
     put_bits(&pb, 1, 1); /* marker */
     if (s->is_vcd && only_for_stream_id==VIDEO_ID) {
         /* This header applies only to the video stream (see VCD standard p. IV-7)*/
@@ -262,7 +270,6 @@ static int mpeg_mux_init(AVFormatContext *ctx)
     dts_id = DTS_ID;
     mpv_id = VIDEO_ID;
     lpcm_id = LPCM_ID;
-    s->scr_stream_index = -1;
     for(i=0;i<ctx->nb_streams;i++) {
         st = ctx->streams[i];
         stream = av_mallocz(sizeof(StreamInfo));
@@ -300,9 +307,6 @@ static int mpeg_mux_init(AVFormatContext *ctx)
             s->audio_bound++;
             break;
         case CODEC_TYPE_VIDEO:
-            /* by default, video is used for the SCR computation */
-            if (s->scr_stream_index == -1)
-                s->scr_stream_index = i;
             stream->id = mpv_id++;
             if (s->is_vcd)
                 /* see VCD standard, p. IV-7*/
@@ -316,24 +320,31 @@ static int mpeg_mux_init(AVFormatContext *ctx)
         default:
             return -1;
         }
+        fifo_init(&stream->fifo, 2*stream->max_buffer_size + 100*MAX_PAYLOAD_SIZE); //FIXME think about the size maybe dynamically realloc
+        stream->next_packet= &stream->premux_packet;
     }
-    /* if no SCR, use first stream (audio) */
-    if (s->scr_stream_index == -1)
-        s->scr_stream_index = 0;
-
     bitrate = 0;
     audio_bitrate = 0;
     video_bitrate = 0;
     for(i=0;i<ctx->nb_streams;i++) {
+        int codec_rate;
         st = ctx->streams[i];
         stream = (StreamInfo*) st->priv_data;
-        
-        bitrate += st->codec.bit_rate;
+
+        if(st->codec.rc_max_rate || stream->id==VIDEO_ID)
+            codec_rate= st->codec.rc_max_rate;
+        else
+            codec_rate= st->codec.bit_rate;
+                
+        if(!codec_rate)
+            codec_rate= (1<<21)*8*50/ctx->nb_streams;
+            
+        bitrate += codec_rate;
 
         if (stream->id==AUDIO_ID)
-            audio_bitrate += st->codec.bit_rate;
+            audio_bitrate += codec_rate;
         else if (stream->id==VIDEO_ID)
-            video_bitrate += st->codec.bit_rate;
+            video_bitrate += codec_rate;
     }
 
     if (s->is_vcd) {
@@ -367,7 +378,8 @@ static int mpeg_mux_init(AVFormatContext *ctx)
     } else {
         /* we increase slightly the bitrate to take into account the
            headers. XXX: compute it exactly */
-        bitrate += 2000;
+        bitrate += bitrate*5/100;
+        bitrate += 10000;
         s->mux_rate = (bitrate + (8 * 50) - 1) / (8 * 50);
     }
     
@@ -395,7 +407,6 @@ static int mpeg_mux_init(AVFormatContext *ctx)
     
     for(i=0;i<ctx->nb_streams;i++) {
         stream = ctx->streams[i]->priv_data;
-        stream->buffer_ptr = 0;
         stream->packet_number = 0;
         stream->start_pts = AV_NOPTS_VALUE;
         stream->start_dts = AV_NOPTS_VALUE;
@@ -432,7 +443,7 @@ static int get_vcd_padding_size(AVFormatContext *ctx, int64_t pts)
     {
         int64_t full_pad_bytes;
         
-        full_pad_bytes = (int64_t)((s->vcd_padding_bitrate * (pts / 90000.0)) / 8.0);
+        full_pad_bytes = (int64_t)((s->vcd_padding_bitrate * (pts / 90000.0)) / 8.0); //FIXME this is wrong
         pad_bytes = (int) (full_pad_bytes - s->vcd_padding_bytes_written);
 
         if (pad_bytes<0)
@@ -547,10 +558,23 @@ static void put_padding_packet(AVFormatContext *ctx, ByteIOContext *pb,int packe
         put_byte(pb, 0xff);
 }
 
+static int get_nb_frames(AVFormatContext *ctx, StreamInfo *stream, int len){
+    int nb_frames=0;
+    PacketDesc *pkt_desc= stream->premux_packet;
+
+    while(len>0){ 
+        if(pkt_desc->size == pkt_desc->unwritten_size)
+            nb_frames++;
+        len -= pkt_desc->unwritten_size;
+        pkt_desc= pkt_desc->next;
+    }
+
+    return nb_frames;
+}
 
 /* flush the packet on stream stream_index */
-static void flush_packet(AVFormatContext *ctx, int stream_index, 
-                         int64_t pts, int64_t dts, int64_t scr)
+static int flush_packet(AVFormatContext *ctx, int stream_index, 
+                         int64_t pts, int64_t dts, int64_t scr, int trailer_size)
 {
     MpegMuxContext *s = ctx->priv_data;
     StreamInfo *stream = ctx->streams[stream_index]->priv_data;
@@ -562,6 +586,7 @@ static void flush_packet(AVFormatContext *ctx, int stream_index,
     int pad_packet_bytes = 0;
     int pes_flags;
     int general_pack = 0;  /*"general" pack without data specific to one stream?*/
+    int nb_frames;
     
     id = stream->id;
     
@@ -572,10 +597,11 @@ static void flush_packet(AVFormatContext *ctx, int stream_index,
 
     buf_ptr = buffer;
 
-    if (((s->packet_number % s->pack_header_freq) == 0)) {
+    if ((s->packet_number % s->pack_header_freq) == 0 || s->last_scr != scr) {
         /* output pack and systems header if needed */
         size = put_pack_header(ctx, buf_ptr, scr);
         buf_ptr += size;
+        s->last_scr= scr;
 
         if (s->is_vcd) {
             /* there is exactly one system header for each stream in a VCD MPEG,
@@ -652,7 +678,23 @@ static void flush_packet(AVFormatContext *ctx, int stream_index,
             startcode = 0x100 + id;
         }
 
-        stuffing_size = payload_size - stream->buffer_ptr;
+        stuffing_size = payload_size - fifo_size(&stream->fifo, stream->fifo.rptr);
+
+        // first byte doesnt fit -> reset pts/dts + stuffing
+        if(payload_size <= trailer_size && pts != AV_NOPTS_VALUE){
+            int timestamp_len=0;
+            if(dts != pts) 
+                timestamp_len += 5;
+            if(pts != AV_NOPTS_VALUE)
+                timestamp_len += s->is_mpeg2 ? 5 : 4;
+            pts=dts= AV_NOPTS_VALUE;
+            header_len -= timestamp_len;
+            payload_size += timestamp_len;
+            stuffing_size += timestamp_len;
+            if(payload_size > trailer_size)
+                stuffing_size += payload_size - trailer_size;
+        }
+
         if (stuffing_size < 0)
             stuffing_size = 0;
         if (stuffing_size > 16) {    /*<=16 for MPEG-1, <=32 for MPEG-2*/
@@ -661,6 +703,8 @@ static void flush_packet(AVFormatContext *ctx, int stream_index,
             payload_size -= stuffing_size;
             stuffing_size = 0;
         }
+        
+        nb_frames= get_nb_frames(ctx, stream, payload_size - stuffing_size);
 
         put_be32(&ctx->pb, startcode);
 
@@ -739,13 +783,17 @@ static void flush_packet(AVFormatContext *ctx, int stream_index,
                 put_byte(&ctx->pb, stream->lpcm_header[2]);
             } else {
                 /* AC3 */
-                put_byte(&ctx->pb, stream->nb_frames);
-                put_be16(&ctx->pb, stream->frame_start_offset);
+                put_byte(&ctx->pb, nb_frames);
+                put_be16(&ctx->pb, trailer_size+1);
             }
         }
 
         /* output data */
-        put_buffer(&ctx->pb, stream->buffer, payload_size - stuffing_size);
+        if(put_fifo(&ctx->pb, &stream->fifo, payload_size - stuffing_size, &stream->fifo.rptr) < 0)
+            return -1;
+    }else{
+        payload_size=
+        stuffing_size= 0;
     }
 
     if (pad_packet_bytes > 0)
@@ -763,8 +811,8 @@ static void flush_packet(AVFormatContext *ctx, int stream_index,
        or some data.*/
     if (!general_pack)
         stream->packet_number++;
-    stream->nb_frames = 0;
-    stream->frame_start_offset = 0;
+    
+    return payload_size - stuffing_size;
 }
 
 static void put_vcd_padding_sector(AVFormatContext *ctx)
@@ -832,22 +880,11 @@ static int64_t update_scr(AVFormatContext *ctx,int stream_index,int64_t pts)
 
         /* XXX: system clock should be computed precisely, especially for
         CBR case. The current mode gives at least something coherent */
-        if (stream_index == s->scr_stream_index
+        if (stream_index == 0
             && pts != AV_NOPTS_VALUE)
             scr = pts;
         else
             scr = s->last_scr;
-
-        /* "Sanity hack": make sure that the SCR does not overtake the pts of
-           buffered data that is still waiting to be written.*/
-        for(i=0;i<ctx->nb_streams;i++) {
-            stream = ctx->streams[i]->priv_data;
-            
-            if(scr > stream->start_pts && stream->start_pts!=AV_NOPTS_VALUE) {
-                /* av_log(ctx, AV_LOG_DEBUG, "mpeg: restricting scr to stream pts (scr=%0.3f, stream index=%d, stream_pts=%0.3f).\n", scr/90000.0, i, stream->start_pts / 90000.0); */
-                scr = stream->start_pts;
-            }
-        }
     }
 
     s->last_scr=scr;
@@ -855,6 +892,135 @@ static int64_t update_scr(AVFormatContext *ctx,int stream_index,int64_t pts)
     return scr;
 }    
 
+static int remove_decoded_packets(AVFormatContext *ctx, int64_t scr){
+//    MpegMuxContext *s = ctx->priv_data;
+    int i;
+
+    for(i=0; i<ctx->nb_streams; i++){
+        AVStream *st = ctx->streams[i];
+        StreamInfo *stream = st->priv_data;
+        PacketDesc *pkt_desc= stream->predecode_packet;
+        
+        while(pkt_desc && scr > pkt_desc->dts){ //FIXME > vs >=
+            if(stream->buffer_index < pkt_desc->size || 
+               stream->predecode_packet == stream->premux_packet){
+                av_log(ctx, AV_LOG_ERROR, "buffer underflow\n");
+                break;
+            }
+            stream->buffer_index -= pkt_desc->size;
+
+            stream->predecode_packet= pkt_desc->next;
+            av_freep(&pkt_desc);
+        }
+    }
+    
+    return 0;
+}
+
+static int output_packet(AVFormatContext *ctx, int flush){
+    MpegMuxContext *s = ctx->priv_data;
+    AVStream *st;
+    StreamInfo *stream;
+    int i, avail_space, es_size, trailer_size;
+    int best_i= -1;
+    int best_score= INT_MIN;
+    int ignore_constraints=0;
+    int64_t scr= s->last_scr;
+
+retry:
+    for(i=0; i<ctx->nb_streams; i++){
+        AVStream *st = ctx->streams[i];
+        StreamInfo *stream = st->priv_data;
+        const int avail_data=  fifo_size(&stream->fifo, stream->fifo.rptr);
+        const int space= stream->max_buffer_size - stream->buffer_index;
+        int rel_space= 1024*space / stream->max_buffer_size;
+
+        if(s->packet_size > avail_data && !flush)
+            return 0;
+        if(avail_data==0)
+            continue;
+        assert(avail_data>0);
+
+        if(space < s->packet_size && !ignore_constraints)
+            continue;
+            
+        if(rel_space > best_score){
+            best_score= rel_space;
+            best_i = i;
+            avail_space= space;
+        }
+    }
+    
+    if(best_i < 0){
+        int64_t best_dts= INT64_MAX;
+
+        for(i=0; i<ctx->nb_streams; i++){
+            AVStream *st = ctx->streams[i];
+            StreamInfo *stream = st->priv_data;
+            PacketDesc *pkt_desc= stream->predecode_packet;
+            if(pkt_desc && pkt_desc->dts < best_dts)
+                best_dts= pkt_desc->dts;
+        }
+
+#if 0
+        av_log(ctx, AV_LOG_DEBUG, "bumping scr, scr:%f, dts:%f\n", 
+               scr/90000.0, best_dts/90000.0);
+#endif
+        if(best_dts == INT64_MAX)
+            return 0;
+
+        if(scr >= best_dts+1 && !ignore_constraints){
+            av_log(ctx, AV_LOG_ERROR, "packet too large, ignoring buffer limits to mux it\n");
+            ignore_constraints= 1;
+        }
+        scr= FFMAX(best_dts+1, scr);
+        if(remove_decoded_packets(ctx, scr) < 0)
+            return -1;
+        goto retry;
+    }
+
+    assert(best_i >= 0);
+    
+    st = ctx->streams[best_i];
+    stream = st->priv_data;
+    
+    assert(fifo_size(&stream->fifo, stream->fifo.rptr) > 0);
+
+    assert(avail_space >= s->packet_size || ignore_constraints);
+    
+    if(stream->premux_packet->unwritten_size == stream->premux_packet->size)
+        trailer_size= 0;
+    else
+        trailer_size= stream->premux_packet->unwritten_size;
+
+    es_size= flush_packet(ctx, best_i, stream->premux_packet->pts, stream->premux_packet->dts, scr, trailer_size);
+
+    if (s->is_vcd) {
+        /* Write one or more padding sectors, if necessary, to reach
+           the constant overall bitrate.*/
+        int vcd_pad_bytes;
+
+        while((vcd_pad_bytes = get_vcd_padding_size(ctx,stream->start_pts) ) >= s->packet_size){ //FIXME pts cannot be correct here
+            put_vcd_padding_sector(ctx);
+            s->last_scr += s->packet_size*90000LL / (s->mux_rate*50LL); //FIXME rounding and first few bytes of each packet
+        }
+    }
+    
+    stream->buffer_index += es_size;
+    s->last_scr += s->packet_size*90000LL / (s->mux_rate*50LL); //FIXME rounding and first few bytes of each packet
+    
+    while(stream->premux_packet && stream->premux_packet->unwritten_size <= es_size){
+        es_size -= stream->premux_packet->unwritten_size;
+        stream->premux_packet= stream->premux_packet->next;
+    }
+    if(es_size)
+        stream->premux_packet->unwritten_size -= es_size;
+    
+    if(remove_decoded_packets(ctx, s->last_scr) < 0)
+        return -1;
+
+    return 1;
+}
 
 static int mpeg_mux_write_packet(AVFormatContext *ctx, AVPacket *pkt)
 {
@@ -866,6 +1032,7 @@ static int mpeg_mux_write_packet(AVFormatContext *ctx, AVPacket *pkt)
     StreamInfo *stream = st->priv_data;
     int64_t pts, dts, new_start_pts, new_start_dts;
     int len, avail_size;
+    PacketDesc *pkt_desc;
     
     pts= pkt->pts;
     dts= pkt->dts;
@@ -891,17 +1058,36 @@ static int mpeg_mux_write_packet(AVFormatContext *ctx, AVPacket *pkt)
            So the real data starts at SCR 36000+3*1200. */
         pts = (pts + 36000 + 3600) & ((1LL << 33) - 1);
         dts = (dts + 36000 + 3600) & ((1LL << 33) - 1);
+    }else{
+        pts = (pts + PRELOAD) & ((1LL << 33) - 1);
+        dts = (dts + PRELOAD) & ((1LL << 33) - 1);
     }
     
-#if 0
-    update_scr(ctx,stream_index,pts);
+    *stream->next_packet=
+    pkt_desc= av_mallocz(sizeof(PacketDesc));
+    pkt_desc->pts= pts;
+    pkt_desc->dts= dts;
+    pkt_desc->unwritten_size=
+    pkt_desc->size= size;
+    if(!stream->predecode_packet)
+        stream->predecode_packet= pkt_desc;
+    stream->next_packet= &pkt_desc->next;
+
+    if(stream->fifo.end - stream->fifo.buffer - fifo_size(&stream->fifo, stream->fifo.rptr) < size){
+        av_log(ctx, AV_LOG_ERROR, "fifo overflow\n");
+        return -1;
+    }
+    fifo_write(&stream->fifo, buf, size, &stream->fifo.wptr);
 
-    printf("%d: pts=%0.3f dts=%0.3f scr=%0.3f\n", 
-           stream_index, 
-           pts / 90000.0, 
-           dts / 90000.0, 
-           s->last_scr / 90000.0);
-#endif
+    for(;;){
+        int ret= output_packet(ctx, 0);
+        if(ret<0) 
+            return ret;
+        else if(ret==0)
+            break;
+    }
+    
+#if 0
     
     /* we assume here that pts != AV_NOPTS_VALUE */
     new_start_pts = stream->start_pts;
@@ -931,8 +1117,6 @@ static int mpeg_mux_write_packet(AVFormatContext *ctx, AVPacket *pkt)
     stream->start_pts = new_start_pts;
     stream->start_dts = new_start_dts;
     stream->nb_frames++;
-    if (stream->frame_start_offset == 0)
-        stream->frame_start_offset = stream->buffer_ptr + 1;
     while (size > 0) {
         avail_size = get_packet_payload_size(ctx, stream_index,
                                              stream->start_pts, 
@@ -968,27 +1152,22 @@ static int mpeg_mux_write_packet(AVFormatContext *ctx, AVPacket *pkt)
             stream->start_dts = AV_NOPTS_VALUE;
         }
     }
-
+#endif
     return 0;
 }
 
 static int mpeg_mux_end(AVFormatContext *ctx)
 {
-    MpegMuxContext *s = ctx->priv_data;
+//    MpegMuxContext *s = ctx->priv_data;
     StreamInfo *stream;
     int i;
-
-    /* flush each packet */
-    for(i=0;i<ctx->nb_streams;i++) {
-        stream = ctx->streams[i]->priv_data;
-        if (stream->buffer_ptr > 0) {
-            update_scr(ctx,i,stream->start_pts);
-
-            /* NOTE: we can always write the remaining data as it was
-               tested before in mpeg_mux_write_packet() */
-            flush_packet(ctx, i, stream->start_pts, stream->start_dts, 
-                         s->last_scr);
-        }
+    
+    for(;;){
+        int ret= output_packet(ctx, 1);
+        if(ret<0) 
+            return ret;
+        else if(ret==0)
+            break;
     }
 
     /* End header according to MPEG1 systems standard. We do not write
@@ -997,6 +1176,12 @@ static int mpeg_mux_end(AVFormatContext *ctx)
     //put_be32(&ctx->pb, ISO_11172_END_CODE);
     //put_flush_packet(&ctx->pb);
 
+    for(i=0;i<ctx->nb_streams;i++) {
+        stream = ctx->streams[i]->priv_data;
+
+        assert(fifo_size(&stream->fifo, stream->fifo.rptr) == 0);
+        fifo_free(&stream->fifo);
+    }
     return 0;
 }
 #endif //CONFIG_ENCODERS

libavformat/utils.c

@@ -264,6 +264,34 @@ void fifo_write(FifoBuffer *f, uint8_t *buf, int size, uint8_t **wptr_ptr)
     *wptr_ptr = wptr;
 }
 
+/* get data from the fifo (return -1 if not enough data) */
+int put_fifo(ByteIOContext *pb, FifoBuffer *f, int buf_size, uint8_t **rptr_ptr)
+{
+    uint8_t *rptr = *rptr_ptr;
+    int size, len;
+
+    if (f->wptr >= rptr) {
+        size = f->wptr - rptr;
+    } else {
+        size = (f->end - rptr) + (f->wptr - f->buffer);
+    }
+    
+    if (size < buf_size)
+        return -1;
+    while (buf_size > 0) {
+        len = f->end - rptr;
+        if (len > buf_size)
+            len = buf_size;
+        put_buffer(pb, rptr, len);
+        rptr += len;
+        if (rptr >= f->end)
+            rptr = f->buffer;
+        buf_size -= len;
+    }
+    *rptr_ptr = rptr;
+    return 0;
+}
+
 int filename_number_test(const char *filename)
 {
     char buf[1024];

tests/libav.regression.ref

@@ -7,9 +7,9 @@ ffmpeg regression test
 ./data/b-libav.asf CRC=750f18c7
 1cbf838e659d7fc3d3e33f4187b91f6c *./data/b-libav.rm
 360251 ./data/b-libav.rm
-e0a9ed22a34e0277ec77c84e8b64afd9 *./data/b-libav.mpg
+82d8794cc5eaf220b2f260ceacaf3a3b *./data/b-libav.mpg
 387072 ./data/b-libav.mpg
-./data/b-libav.mpg CRC=c0b64225
+./data/b-libav.mpg CRC=16c74225
 57a8dfc7926802bb337a9d8918de94a8 *./data/b-libav.swf
 41816 ./data/b-libav.swf
 ./data/b-libav.swf CRC=2b273fea