[FFmpeg-soc] [soc]: r2015 - dvbmuxer/mpegenc.c
bcoudurier
subversion at mplayerhq.hu
Wed Mar 12 12:07:23 CET 2008
Author: bcoudurier
Date: Wed Mar 12 12:07:23 2008
New Revision: 2015
Log:
add trunk mpegenc.c to easily show differences
Added:
dvbmuxer/mpegenc.c
Added: dvbmuxer/mpegenc.c
==============================================================================
--- (empty file)
+++ dvbmuxer/mpegenc.c Wed Mar 12 12:07:23 2008
@@ -0,0 +1,1294 @@
+/*
+ * MPEG1/2 muxer
+ * Copyright (c) 2000, 2001, 2002 Fabrice Bellard.
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "avformat.h"
+#include "bitstream.h"
+#include "fifo.h"
+#include "mpeg.h"
+
+#define MAX_PAYLOAD_SIZE 4096
+//#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 {
+ AVFifoBuffer 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;
+ uint8_t lpcm_header[3];
+ int lpcm_align;
+ int bytes_to_iframe;
+ int align_iframe;
+ int64_t vobu_start_pts;
+} StreamInfo;
+
+typedef struct {
+ int packet_size; /* required packet size */
+ int packet_number;
+ int pack_header_freq; /* frequency (in packets^-1) at which we send pack headers */
+ int system_header_freq;
+ int system_header_size;
+ int mux_rate; /* bitrate in units of 50 bytes/s */
+ /* stream info */
+ int audio_bound;
+ int video_bound;
+ int is_mpeg2;
+ int is_vcd;
+ int is_svcd;
+ int is_dvd;
+ int64_t last_scr; /* current system clock */
+
+ double vcd_padding_bitrate; //FIXME floats
+ int64_t vcd_padding_bytes_written;
+
+} MpegMuxContext;
+
+extern AVOutputFormat mpeg1vcd_muxer;
+extern AVOutputFormat mpeg2dvd_muxer;
+extern AVOutputFormat mpeg2svcd_muxer;
+extern AVOutputFormat mpeg2vob_muxer;
+
+static int put_pack_header(AVFormatContext *ctx,
+ uint8_t *buf, int64_t timestamp)
+{
+ MpegMuxContext *s = ctx->priv_data;
+ PutBitContext pb;
+
+ init_put_bits(&pb, buf, 128);
+
+ put_bits(&pb, 32, PACK_START_CODE);
+ if (s->is_mpeg2) {
+ put_bits(&pb, 2, 0x1);
+ } else {
+ put_bits(&pb, 4, 0x2);
+ }
+ put_bits(&pb, 3, (uint32_t)((timestamp >> 30) & 0x07));
+ put_bits(&pb, 1, 1);
+ put_bits(&pb, 15, (uint32_t)((timestamp >> 15) & 0x7fff));
+ put_bits(&pb, 1, 1);
+ put_bits(&pb, 15, (uint32_t)((timestamp) & 0x7fff));
+ put_bits(&pb, 1, 1);
+ if (s->is_mpeg2) {
+ /* clock extension */
+ put_bits(&pb, 9, 0);
+ }
+ put_bits(&pb, 1, 1);
+ put_bits(&pb, 22, s->mux_rate);
+ put_bits(&pb, 1, 1);
+ if (s->is_mpeg2) {
+ put_bits(&pb, 1, 1);
+ put_bits(&pb, 5, 0x1f); /* reserved */
+ put_bits(&pb, 3, 0); /* stuffing length */
+ }
+ flush_put_bits(&pb);
+ return pbBufPtr(&pb) - pb.buf;
+}
+
+static int put_system_header(AVFormatContext *ctx, uint8_t *buf,int only_for_stream_id)
+{
+ MpegMuxContext *s = ctx->priv_data;
+ int size, i, private_stream_coded, id;
+ PutBitContext pb;
+
+ init_put_bits(&pb, buf, 128);
+
+ put_bits(&pb, 32, SYSTEM_HEADER_START_CODE);
+ put_bits(&pb, 16, 0);
+ put_bits(&pb, 1, 1);
+
+ 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)*/
+ put_bits(&pb, 6, 0);
+ } else
+ put_bits(&pb, 6, s->audio_bound);
+
+ if (s->is_vcd) {
+ /* see VCD standard, p. IV-7*/
+ put_bits(&pb, 1, 0);
+ put_bits(&pb, 1, 1);
+ } else {
+ put_bits(&pb, 1, 0); /* variable bitrate*/
+ put_bits(&pb, 1, 0); /* non constrainted bit stream */
+ }
+
+ if (s->is_vcd || s->is_dvd) {
+ /* see VCD standard p IV-7 */
+ put_bits(&pb, 1, 1); /* audio locked */
+ put_bits(&pb, 1, 1); /* video locked */
+ } else {
+ put_bits(&pb, 1, 0); /* audio locked */
+ put_bits(&pb, 1, 0); /* video locked */
+ }
+
+ put_bits(&pb, 1, 1); /* marker */
+
+ if (s->is_vcd && only_for_stream_id==AUDIO_ID) {
+ /* This header applies only to the audio stream (see VCD standard p. IV-7)*/
+ put_bits(&pb, 5, 0);
+ } else
+ put_bits(&pb, 5, s->video_bound);
+
+ if (s->is_dvd) {
+ put_bits(&pb, 1, 0); /* packet_rate_restriction_flag */
+ put_bits(&pb, 7, 0x7f); /* reserved byte */
+ } else
+ put_bits(&pb, 8, 0xff); /* reserved byte */
+
+ /* DVD-Video Stream_bound entries
+ id (0xB9) video, maximum P-STD for stream 0xE0. (P-STD_buffer_bound_scale = 1)
+ id (0xB8) audio, maximum P-STD for any MPEG audio (0xC0 to 0xC7) streams. If there are none set to 4096 (32x128). (P-STD_buffer_bound_scale = 0)
+ id (0xBD) private stream 1 (audio other than MPEG and subpictures). (P-STD_buffer_bound_scale = 1)
+ id (0xBF) private stream 2, NAV packs, set to 2x1024. */
+ if (s->is_dvd) {
+
+ int P_STD_max_video = 0;
+ int P_STD_max_mpeg_audio = 0;
+ int P_STD_max_mpeg_PS1 = 0;
+
+ for(i=0;i<ctx->nb_streams;i++) {
+ StreamInfo *stream = ctx->streams[i]->priv_data;
+
+ id = stream->id;
+ if (id == 0xbd && stream->max_buffer_size > P_STD_max_mpeg_PS1) {
+ P_STD_max_mpeg_PS1 = stream->max_buffer_size;
+ } else if (id >= 0xc0 && id <= 0xc7 && stream->max_buffer_size > P_STD_max_mpeg_audio) {
+ P_STD_max_mpeg_audio = stream->max_buffer_size;
+ } else if (id == 0xe0 && stream->max_buffer_size > P_STD_max_video) {
+ P_STD_max_video = stream->max_buffer_size;
+ }
+ }
+
+ /* video */
+ put_bits(&pb, 8, 0xb9); /* stream ID */
+ put_bits(&pb, 2, 3);
+ put_bits(&pb, 1, 1);
+ put_bits(&pb, 13, P_STD_max_video / 1024);
+
+ /* audio */
+ if (P_STD_max_mpeg_audio == 0)
+ P_STD_max_mpeg_audio = 4096;
+ put_bits(&pb, 8, 0xb8); /* stream ID */
+ put_bits(&pb, 2, 3);
+ put_bits(&pb, 1, 0);
+ put_bits(&pb, 13, P_STD_max_mpeg_audio / 128);
+
+ /* private stream 1 */
+ put_bits(&pb, 8, 0xbd); /* stream ID */
+ put_bits(&pb, 2, 3);
+ put_bits(&pb, 1, 0);
+ put_bits(&pb, 13, P_STD_max_mpeg_PS1 / 128);
+
+ /* private stream 2 */
+ put_bits(&pb, 8, 0xbf); /* stream ID */
+ put_bits(&pb, 2, 3);
+ put_bits(&pb, 1, 1);
+ put_bits(&pb, 13, 2);
+ }
+ else {
+ /* audio stream info */
+ private_stream_coded = 0;
+ for(i=0;i<ctx->nb_streams;i++) {
+ StreamInfo *stream = ctx->streams[i]->priv_data;
+
+
+ /* For VCDs, only include the stream info for the stream
+ that the pack which contains this system belongs to.
+ (see VCD standard p. IV-7) */
+ if ( !s->is_vcd || stream->id==only_for_stream_id
+ || only_for_stream_id==0) {
+
+ id = stream->id;
+ if (id < 0xc0) {
+ /* special case for private streams (AC3 use that) */
+ if (private_stream_coded)
+ continue;
+ private_stream_coded = 1;
+ id = 0xbd;
+ }
+ put_bits(&pb, 8, id); /* stream ID */
+ put_bits(&pb, 2, 3);
+ if (id < 0xe0) {
+ /* audio */
+ put_bits(&pb, 1, 0);
+ put_bits(&pb, 13, stream->max_buffer_size / 128);
+ } else {
+ /* video */
+ put_bits(&pb, 1, 1);
+ put_bits(&pb, 13, stream->max_buffer_size / 1024);
+ }
+ }
+ }
+ }
+
+ flush_put_bits(&pb);
+ size = pbBufPtr(&pb) - pb.buf;
+ /* patch packet size */
+ buf[4] = (size - 6) >> 8;
+ buf[5] = (size - 6) & 0xff;
+
+ return size;
+}
+
+static int get_system_header_size(AVFormatContext *ctx)
+{
+ int buf_index, i, private_stream_coded;
+ StreamInfo *stream;
+ MpegMuxContext *s = ctx->priv_data;
+
+ if (s->is_dvd)
+ return 18; // DVD-Video system headers are 18 bytes fixed length.
+
+ buf_index = 12;
+ private_stream_coded = 0;
+ for(i=0;i<ctx->nb_streams;i++) {
+ stream = ctx->streams[i]->priv_data;
+ if (stream->id < 0xc0) {
+ if (private_stream_coded)
+ continue;
+ private_stream_coded = 1;
+ }
+ buf_index += 3;
+ }
+ return buf_index;
+}
+
+static int mpeg_mux_init(AVFormatContext *ctx)
+{
+ MpegMuxContext *s = ctx->priv_data;
+ int bitrate, i, mpa_id, mpv_id, mps_id, ac3_id, dts_id, lpcm_id, j;
+ AVStream *st;
+ StreamInfo *stream;
+ int audio_bitrate;
+ int video_bitrate;
+
+ s->packet_number = 0;
+ s->is_vcd = (ENABLE_MPEG1VCD_MUXER && ctx->oformat == &mpeg1vcd_muxer);
+ s->is_svcd = (ENABLE_MPEG2SVCD_MUXER && ctx->oformat == &mpeg2svcd_muxer);
+ s->is_mpeg2 = ((ENABLE_MPEG2VOB_MUXER && ctx->oformat == &mpeg2vob_muxer) ||
+ (ENABLE_MPEG2DVD_MUXER && ctx->oformat == &mpeg2dvd_muxer) ||
+ (ENABLE_MPEG2SVCD_MUXER && ctx->oformat == &mpeg2svcd_muxer));
+ s->is_dvd = (ENABLE_MPEG2DVD_MUXER && ctx->oformat == &mpeg2dvd_muxer);
+
+ if(ctx->packet_size)
+ s->packet_size = ctx->packet_size;
+ else
+ s->packet_size = 2048;
+
+ s->vcd_padding_bytes_written = 0;
+ s->vcd_padding_bitrate=0;
+
+ s->audio_bound = 0;
+ s->video_bound = 0;
+ mpa_id = AUDIO_ID;
+ ac3_id = AC3_ID;
+ dts_id = DTS_ID;
+ mpv_id = VIDEO_ID;
+ mps_id = SUB_ID;
+ lpcm_id = LPCM_ID;
+ for(i=0;i<ctx->nb_streams;i++) {
+ st = ctx->streams[i];
+ stream = av_mallocz(sizeof(StreamInfo));
+ if (!stream)
+ goto fail;
+ st->priv_data = stream;
+
+ av_set_pts_info(st, 64, 1, 90000);
+
+ switch(st->codec->codec_type) {
+ case CODEC_TYPE_AUDIO:
+ if (st->codec->codec_id == CODEC_ID_AC3) {
+ stream->id = ac3_id++;
+ } else if (st->codec->codec_id == CODEC_ID_DTS) {
+ stream->id = dts_id++;
+ } else if (st->codec->codec_id == CODEC_ID_PCM_S16BE) {
+ stream->id = lpcm_id++;
+ for(j = 0; j < 4; j++) {
+ if (lpcm_freq_tab[j] == st->codec->sample_rate)
+ break;
+ }
+ if (j == 4)
+ goto fail;
+ if (st->codec->channels > 8)
+ return -1;
+ stream->lpcm_header[0] = 0x0c;
+ stream->lpcm_header[1] = (st->codec->channels - 1) | (j << 4);
+ stream->lpcm_header[2] = 0x80;
+ stream->lpcm_align = st->codec->channels * 2;
+ } else {
+ stream->id = mpa_id++;
+ }
+
+ /* This value HAS to be used for VCD (see VCD standard, p. IV-7).
+ Right now it is also used for everything else.*/
+ stream->max_buffer_size = 4 * 1024;
+ s->audio_bound++;
+ break;
+ case CODEC_TYPE_VIDEO:
+ stream->id = mpv_id++;
+ if (st->codec->rc_buffer_size)
+ stream->max_buffer_size = 6*1024 + st->codec->rc_buffer_size/8;
+ else
+ stream->max_buffer_size = 230*1024; //FIXME this is probably too small as default
+#if 0
+ /* see VCD standard, p. IV-7*/
+ stream->max_buffer_size = 46 * 1024;
+ else
+ /* This value HAS to be used for SVCD (see SVCD standard, p. 26 V.2.3.2).
+ Right now it is also used for everything else.*/
+ stream->max_buffer_size = 230 * 1024;
+#endif
+ s->video_bound++;
+ break;
+ case CODEC_TYPE_SUBTITLE:
+ stream->id = mps_id++;
+ stream->max_buffer_size = 16 * 1024;
+ break;
+ default:
+ return -1;
+ }
+ av_fifo_init(&stream->fifo, 16);
+ }
+ 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;
+
+ 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 += codec_rate;
+ else if (stream->id==VIDEO_ID)
+ video_bitrate += codec_rate;
+ }
+
+ if(ctx->mux_rate){
+ s->mux_rate= (ctx->mux_rate + (8 * 50) - 1) / (8 * 50);
+ } else {
+ /* we increase slightly the bitrate to take into account the
+ headers. XXX: compute it exactly */
+ bitrate += bitrate*5/100;
+ bitrate += 10000;
+ s->mux_rate = (bitrate + (8 * 50) - 1) / (8 * 50);
+ }
+
+ if (s->is_vcd) {
+ double overhead_rate;
+
+ /* The VCD standard mandates that the mux_rate field is 3528
+ (see standard p. IV-6).
+ The value is actually "wrong", i.e. if you calculate
+ it using the normal formula and the 75 sectors per second transfer
+ rate you get a different value because the real pack size is 2324,
+ not 2352. But the standard explicitly specifies that the mux_rate
+ field in the header must have this value.*/
+// s->mux_rate=2352 * 75 / 50; /* = 3528*/
+
+ /* The VCD standard states that the muxed stream must be
+ exactly 75 packs / second (the data rate of a single speed cdrom).
+ Since the video bitrate (probably 1150000 bits/sec) will be below
+ the theoretical maximum we have to add some padding packets
+ to make up for the lower data rate.
+ (cf. VCD standard p. IV-6 )*/
+
+ /* Add the header overhead to the data rate.
+ 2279 data bytes per audio pack, 2294 data bytes per video pack*/
+ overhead_rate = ((audio_bitrate / 8.0) / 2279) * (2324 - 2279);
+ overhead_rate += ((video_bitrate / 8.0) / 2294) * (2324 - 2294);
+ overhead_rate *= 8;
+
+ /* Add padding so that the full bitrate is 2324*75 bytes/sec */
+ s->vcd_padding_bitrate = 2324 * 75 * 8 - (bitrate + overhead_rate);
+ }
+
+ if (s->is_vcd || s->is_mpeg2)
+ /* every packet */
+ s->pack_header_freq = 1;
+ else
+ /* every 2 seconds */
+ s->pack_header_freq = 2 * bitrate / s->packet_size / 8;
+
+ /* the above seems to make pack_header_freq zero sometimes */
+ if (s->pack_header_freq == 0)
+ s->pack_header_freq = 1;
+
+ if (s->is_mpeg2)
+ /* every 200 packets. Need to look at the spec. */
+ s->system_header_freq = s->pack_header_freq * 40;
+ else if (s->is_vcd)
+ /* the standard mandates that there are only two system headers
+ in the whole file: one in the first packet of each stream.
+ (see standard p. IV-7 and IV-8) */
+ s->system_header_freq = 0x7fffffff;
+ else
+ s->system_header_freq = s->pack_header_freq * 5;
+
+ for(i=0;i<ctx->nb_streams;i++) {
+ stream = ctx->streams[i]->priv_data;
+ stream->packet_number = 0;
+ }
+ s->system_header_size = get_system_header_size(ctx);
+ s->last_scr = 0;
+ return 0;
+ fail:
+ for(i=0;i<ctx->nb_streams;i++) {
+ av_free(ctx->streams[i]->priv_data);
+ }
+ return AVERROR(ENOMEM);
+}
+
+static inline void put_timestamp(ByteIOContext *pb, int id, int64_t timestamp)
+{
+ put_byte(pb,
+ (id << 4) |
+ (((timestamp >> 30) & 0x07) << 1) |
+ 1);
+ put_be16(pb, (uint16_t)((((timestamp >> 15) & 0x7fff) << 1) | 1));
+ put_be16(pb, (uint16_t)((((timestamp) & 0x7fff) << 1) | 1));
+}
+
+
+/* return the number of padding bytes that should be inserted into
+ the multiplexed stream.*/
+static int get_vcd_padding_size(AVFormatContext *ctx, int64_t pts)
+{
+ MpegMuxContext *s = ctx->priv_data;
+ int pad_bytes = 0;
+
+ if (s->vcd_padding_bitrate > 0 && pts!=AV_NOPTS_VALUE)
+ {
+ int64_t full_pad_bytes;
+
+ 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)
+ /* might happen if we have already padded to a later timestamp. This
+ can occur if another stream has already advanced further.*/
+ pad_bytes=0;
+ }
+
+ return pad_bytes;
+}
+
+
+#if 0 /* unused, remove? */
+/* return the exact available payload size for the next packet for
+ stream 'stream_index'. 'pts' and 'dts' are only used to know if
+ timestamps are needed in the packet header. */
+static int get_packet_payload_size(AVFormatContext *ctx, int stream_index,
+ int64_t pts, int64_t dts)
+{
+ MpegMuxContext *s = ctx->priv_data;
+ int buf_index;
+ StreamInfo *stream;
+
+ stream = ctx->streams[stream_index]->priv_data;
+
+ buf_index = 0;
+ if (((s->packet_number % s->pack_header_freq) == 0)) {
+ /* pack header size */
+ if (s->is_mpeg2)
+ buf_index += 14;
+ else
+ buf_index += 12;
+
+ if (s->is_vcd) {
+ /* there is exactly one system header for each stream in a VCD MPEG,
+ One in the very first video packet and one in the very first
+ audio packet (see VCD standard p. IV-7 and IV-8).*/
+
+ if (stream->packet_number==0)
+ /* The system headers refer only to the stream they occur in,
+ so they have a constant size.*/
+ buf_index += 15;
+
+ } else {
+ if ((s->packet_number % s->system_header_freq) == 0)
+ buf_index += s->system_header_size;
+ }
+ }
+
+ if ((s->is_vcd && stream->packet_number==0)
+ || (s->is_svcd && s->packet_number==0))
+ /* the first pack of each stream contains only the pack header,
+ the system header and some padding (see VCD standard p. IV-6)
+ Add the padding size, so that the actual payload becomes 0.*/
+ buf_index += s->packet_size - buf_index;
+ else {
+ /* packet header size */
+ buf_index += 6;
+ if (s->is_mpeg2) {
+ buf_index += 3;
+ if (stream->packet_number==0)
+ buf_index += 3; /* PES extension */
+ buf_index += 1; /* obligatory stuffing byte */
+ }
+ if (pts != AV_NOPTS_VALUE) {
+ if (dts != pts)
+ buf_index += 5 + 5;
+ else
+ buf_index += 5;
+
+ } else {
+ if (!s->is_mpeg2)
+ buf_index++;
+ }
+
+ if (stream->id < 0xc0) {
+ /* AC3/LPCM private data header */
+ buf_index += 4;
+ if (stream->id >= 0xa0) {
+ int n;
+ buf_index += 3;
+ /* NOTE: we round the payload size to an integer number of
+ LPCM samples */
+ n = (s->packet_size - buf_index) % stream->lpcm_align;
+ if (n)
+ buf_index += (stream->lpcm_align - n);
+ }
+ }
+
+ if (s->is_vcd && stream->id == AUDIO_ID)
+ /* The VCD standard demands that 20 zero bytes follow
+ each audio packet (see standard p. IV-8).*/
+ buf_index+=20;
+ }
+ return s->packet_size - buf_index;
+}
+#endif
+
+/* Write an MPEG padding packet header. */
+static void put_padding_packet(AVFormatContext *ctx, ByteIOContext *pb,int packet_bytes)
+{
+ MpegMuxContext *s = ctx->priv_data;
+ int i;
+
+ put_be32(pb, PADDING_STREAM);
+ put_be16(pb, packet_bytes - 6);
+ if (!s->is_mpeg2) {
+ put_byte(pb, 0x0f);
+ packet_bytes -= 7;
+ } else
+ packet_bytes -= 6;
+
+ for(i=0;i<packet_bytes;i++)
+ 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 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;
+ uint8_t *buf_ptr;
+ int size, payload_size, startcode, id, stuffing_size, i, header_len;
+ int packet_size;
+ uint8_t buffer[128];
+ int zero_trail_bytes = 0;
+ 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;
+
+#if 0
+ printf("packet ID=%2x PTS=%0.3f\n",
+ id, pts / 90000.0);
+#endif
+
+ buf_ptr = buffer;
+
+ 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,
+ One in the very first video packet and one in the very first
+ audio packet (see VCD standard p. IV-7 and IV-8).*/
+
+ if (stream->packet_number==0) {
+ size = put_system_header(ctx, buf_ptr, id);
+ buf_ptr += size;
+ }
+ } else if (s->is_dvd) {
+ if (stream->align_iframe || s->packet_number == 0){
+ int PES_bytes_to_fill = s->packet_size - size - 10;
+
+ if (pts != AV_NOPTS_VALUE) {
+ if (dts != pts)
+ PES_bytes_to_fill -= 5 + 5;
+ else
+ PES_bytes_to_fill -= 5;
+ }
+
+ if (stream->bytes_to_iframe == 0 || s->packet_number == 0) {
+ size = put_system_header(ctx, buf_ptr, 0);
+ buf_ptr += size;
+ size = buf_ptr - buffer;
+ put_buffer(ctx->pb, buffer, size);
+
+ put_be32(ctx->pb, PRIVATE_STREAM_2);
+ put_be16(ctx->pb, 0x03d4); // length
+ put_byte(ctx->pb, 0x00); // substream ID, 00=PCI
+ for (i = 0; i < 979; i++)
+ put_byte(ctx->pb, 0x00);
+
+ put_be32(ctx->pb, PRIVATE_STREAM_2);
+ put_be16(ctx->pb, 0x03fa); // length
+ put_byte(ctx->pb, 0x01); // substream ID, 01=DSI
+ for (i = 0; i < 1017; i++)
+ put_byte(ctx->pb, 0x00);
+
+ memset(buffer, 0, 128);
+ buf_ptr = buffer;
+ s->packet_number++;
+ stream->align_iframe = 0;
+ scr += s->packet_size*90000LL / (s->mux_rate*50LL); //FIXME rounding and first few bytes of each packet
+ size = put_pack_header(ctx, buf_ptr, scr);
+ s->last_scr= scr;
+ buf_ptr += size;
+ /* GOP Start */
+ } else if (stream->bytes_to_iframe < PES_bytes_to_fill) {
+ pad_packet_bytes = PES_bytes_to_fill - stream->bytes_to_iframe;
+ }
+ }
+ } else {
+ if ((s->packet_number % s->system_header_freq) == 0) {
+ size = put_system_header(ctx, buf_ptr, 0);
+ buf_ptr += size;
+ }
+ }
+ }
+ size = buf_ptr - buffer;
+ put_buffer(ctx->pb, buffer, size);
+
+ packet_size = s->packet_size - size;
+
+ if (s->is_vcd && id == AUDIO_ID)
+ /* The VCD standard demands that 20 zero bytes follow
+ each audio pack (see standard p. IV-8).*/
+ zero_trail_bytes += 20;
+
+ if ((s->is_vcd && stream->packet_number==0)
+ || (s->is_svcd && s->packet_number==0)) {
+ /* for VCD the first pack of each stream contains only the pack header,
+ the system header and lots of padding (see VCD standard p. IV-6).
+ In the case of an audio pack, 20 zero bytes are also added at
+ the end.*/
+ /* For SVCD we fill the very first pack to increase compatibility with
+ some DVD players. Not mandated by the standard.*/
+ if (s->is_svcd)
+ general_pack = 1; /* the system header refers to both streams and no stream data*/
+ pad_packet_bytes = packet_size - zero_trail_bytes;
+ }
+
+ packet_size -= pad_packet_bytes + zero_trail_bytes;
+
+ if (packet_size > 0) {
+
+ /* packet header size */
+ packet_size -= 6;
+
+ /* packet header */
+ if (s->is_mpeg2) {
+ header_len = 3;
+ if (stream->packet_number==0)
+ header_len += 3; /* PES extension */
+ header_len += 1; /* obligatory stuffing byte */
+ } else {
+ header_len = 0;
+ }
+ if (pts != AV_NOPTS_VALUE) {
+ if (dts != pts)
+ header_len += 5 + 5;
+ else
+ header_len += 5;
+ } else {
+ if (!s->is_mpeg2)
+ header_len++;
+ }
+
+ payload_size = packet_size - header_len;
+ if (id < 0xc0) {
+ startcode = PRIVATE_STREAM_1;
+ payload_size -= 1;
+ if (id >= 0x40) {
+ payload_size -= 3;
+ if (id >= 0xa0)
+ payload_size -= 3;
+ }
+ } else {
+ startcode = 0x100 + id;
+ }
+
+ stuffing_size = payload_size - av_fifo_size(&stream->fifo);
+
+ // first byte does not 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;
+ if (s->is_dvd && stream->align_iframe) {
+ pad_packet_bytes += timestamp_len;
+ packet_size -= timestamp_len;
+ } else {
+ payload_size += timestamp_len;
+ }
+ stuffing_size += timestamp_len;
+ if(payload_size > trailer_size)
+ stuffing_size += payload_size - trailer_size;
+ }
+
+ if (pad_packet_bytes > 0 && pad_packet_bytes <= 7) { // can't use padding, so use stuffing
+ packet_size += pad_packet_bytes;
+ payload_size += pad_packet_bytes; // undo the previous adjustment
+ if (stuffing_size < 0) {
+ stuffing_size = pad_packet_bytes;
+ } else {
+ stuffing_size += pad_packet_bytes;
+ }
+ pad_packet_bytes = 0;
+ }
+
+ if (stuffing_size < 0)
+ stuffing_size = 0;
+ if (stuffing_size > 16) { /*<=16 for MPEG-1, <=32 for MPEG-2*/
+ pad_packet_bytes += stuffing_size;
+ packet_size -= stuffing_size;
+ payload_size -= stuffing_size;
+ stuffing_size = 0;
+ }
+
+ nb_frames= get_nb_frames(ctx, stream, payload_size - stuffing_size);
+
+ put_be32(ctx->pb, startcode);
+
+ put_be16(ctx->pb, packet_size);
+
+ if (!s->is_mpeg2)
+ for(i=0;i<stuffing_size;i++)
+ put_byte(ctx->pb, 0xff);
+
+ if (s->is_mpeg2) {
+ put_byte(ctx->pb, 0x80); /* mpeg2 id */
+
+ pes_flags=0;
+
+ if (pts != AV_NOPTS_VALUE) {
+ pes_flags |= 0x80;
+ if (dts != pts)
+ pes_flags |= 0x40;
+ }
+
+ /* Both the MPEG-2 and the SVCD standards demand that the
+ P-STD_buffer_size field be included in the first packet of
+ every stream. (see SVCD standard p. 26 V.2.3.1 and V.2.3.2
+ and MPEG-2 standard 2.7.7) */
+ if (stream->packet_number == 0)
+ pes_flags |= 0x01;
+
+ put_byte(ctx->pb, pes_flags); /* flags */
+ put_byte(ctx->pb, header_len - 3 + stuffing_size);
+
+ if (pes_flags & 0x80) /*write pts*/
+ put_timestamp(ctx->pb, (pes_flags & 0x40) ? 0x03 : 0x02, pts);
+ if (pes_flags & 0x40) /*write dts*/
+ put_timestamp(ctx->pb, 0x01, dts);
+
+ if (pes_flags & 0x01) { /*write pes extension*/
+ put_byte(ctx->pb, 0x10); /* flags */
+
+ /* P-STD buffer info */
+ if (id == AUDIO_ID)
+ put_be16(ctx->pb, 0x4000 | stream->max_buffer_size/128);
+ else
+ put_be16(ctx->pb, 0x6000 | stream->max_buffer_size/1024);
+ }
+
+ } else {
+ if (pts != AV_NOPTS_VALUE) {
+ if (dts != pts) {
+ put_timestamp(ctx->pb, 0x03, pts);
+ put_timestamp(ctx->pb, 0x01, dts);
+ } else {
+ put_timestamp(ctx->pb, 0x02, pts);
+ }
+ } else {
+ put_byte(ctx->pb, 0x0f);
+ }
+ }
+
+ if (s->is_mpeg2) {
+ /* special stuffing byte that is always written
+ to prevent accidental generation of start codes. */
+ put_byte(ctx->pb, 0xff);
+
+ for(i=0;i<stuffing_size;i++)
+ put_byte(ctx->pb, 0xff);
+ }
+
+ if (startcode == PRIVATE_STREAM_1) {
+ put_byte(ctx->pb, id);
+ if (id >= 0xa0) {
+ /* LPCM (XXX: check nb_frames) */
+ put_byte(ctx->pb, 7);
+ put_be16(ctx->pb, 4); /* skip 3 header bytes */
+ put_byte(ctx->pb, stream->lpcm_header[0]);
+ put_byte(ctx->pb, stream->lpcm_header[1]);
+ put_byte(ctx->pb, stream->lpcm_header[2]);
+ } else if (id >= 0x40) {
+ /* AC3 */
+ put_byte(ctx->pb, nb_frames);
+ put_be16(ctx->pb, trailer_size+1);
+ }
+ }
+
+ /* output data */
+ if(av_fifo_generic_read(&stream->fifo, payload_size - stuffing_size, &put_buffer, ctx->pb) < 0)
+ return -1;
+ stream->bytes_to_iframe -= payload_size - stuffing_size;
+ }else{
+ payload_size=
+ stuffing_size= 0;
+ }
+
+ if (pad_packet_bytes > 0)
+ put_padding_packet(ctx,ctx->pb, pad_packet_bytes);
+
+ for(i=0;i<zero_trail_bytes;i++)
+ put_byte(ctx->pb, 0x00);
+
+ put_flush_packet(ctx->pb);
+
+ s->packet_number++;
+
+ /* only increase the stream packet number if this pack actually contains
+ something that is specific to this stream! I.e. a dedicated header
+ or some data.*/
+ if (!general_pack)
+ stream->packet_number++;
+
+ return payload_size - stuffing_size;
+}
+
+static void put_vcd_padding_sector(AVFormatContext *ctx)
+{
+ /* There are two ways to do this padding: writing a sector/pack
+ of 0 values, or writing an MPEG padding pack. Both seem to
+ work with most decoders, BUT the VCD standard only allows a 0-sector
+ (see standard p. IV-4, IV-5).
+ So a 0-sector it is...*/
+
+ MpegMuxContext *s = ctx->priv_data;
+ int i;
+
+ for(i=0;i<s->packet_size;i++)
+ put_byte(ctx->pb, 0);
+
+ s->vcd_padding_bytes_written += s->packet_size;
+
+ put_flush_packet(ctx->pb);
+
+ /* increasing the packet number is correct. The SCR of the following packs
+ is calculated from the packet_number and it has to include the padding
+ sector (it represents the sector index, not the MPEG pack index)
+ (see VCD standard p. IV-6)*/
+ s->packet_number++;
+}
+
+#if 0 /* unused, remove? */
+static int64_t get_vcd_scr(AVFormatContext *ctx,int stream_index,int64_t pts)
+{
+ MpegMuxContext *s = ctx->priv_data;
+ int64_t scr;
+
+ /* Since the data delivery rate is constant, SCR is computed
+ using the formula C + i * 1200 where C is the start constant
+ and i is the pack index.
+ It is recommended that SCR 0 is at the beginning of the VCD front
+ margin (a sequence of empty Form 2 sectors on the CD).
+ It is recommended that the front margin is 30 sectors long, so
+ we use C = 30*1200 = 36000
+ (Note that even if the front margin is not 30 sectors the file
+ will still be correct according to the standard. It just won't have
+ the "recommended" value).*/
+ scr = 36000 + s->packet_number * 1200;
+
+ return scr;
+}
+#endif
+
+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;
+
+ while((pkt_desc= stream->predecode_packet)
+ && 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 i=%d bufi=%d size=%d\n",
+ i, stream->buffer_index, pkt_desc->size);
+ 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=0, es_size, trailer_size;
+ int best_i= -1;
+ int best_score= INT_MIN;
+ int ignore_constraints=0;
+ int64_t scr= s->last_scr;
+ PacketDesc *timestamp_packet;
+ const int64_t max_delay= av_rescale(ctx->max_delay, 90000, AV_TIME_BASE);
+
+retry:
+ for(i=0; i<ctx->nb_streams; i++){
+ AVStream *st = ctx->streams[i];
+ StreamInfo *stream = st->priv_data;
+ const int avail_data= av_fifo_size(&stream->fifo);
+ const int space= stream->max_buffer_size - stream->buffer_index;
+ int rel_space= 1024*space / stream->max_buffer_size;
+ PacketDesc *next_pkt= stream->premux_packet;
+
+ /* for subtitle, a single PES packet must be generated,
+ so we flush after every single subtitle packet */
+ if(s->packet_size > avail_data && !flush
+ && st->codec->codec_type != CODEC_TYPE_SUBTITLE)
+ return 0;
+ if(avail_data==0)
+ continue;
+ assert(avail_data>0);
+
+ if(space < s->packet_size && !ignore_constraints)
+ continue;
+
+ if(next_pkt && next_pkt->dts - scr > max_delay)
+ 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(av_fifo_size(&stream->fifo) > 0);
+
+ assert(avail_space >= s->packet_size || ignore_constraints);
+
+ timestamp_packet= stream->premux_packet;
+ if(timestamp_packet->unwritten_size == timestamp_packet->size){
+ trailer_size= 0;
+ }else{
+ trailer_size= timestamp_packet->unwritten_size;
+ timestamp_packet= timestamp_packet->next;
+ }
+
+ if(timestamp_packet){
+//av_log(ctx, AV_LOG_DEBUG, "dts:%f pts:%f scr:%f stream:%d\n", timestamp_packet->dts/90000.0, timestamp_packet->pts/90000.0, scr/90000.0, best_i);
+ es_size= flush_packet(ctx, best_i, timestamp_packet->pts, timestamp_packet->dts, scr, trailer_size);
+ }else{
+ assert(av_fifo_size(&stream->fifo) == trailer_size);
+ es_size= flush_packet(ctx, best_i, AV_NOPTS_VALUE, AV_NOPTS_VALUE, 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->premux_packet->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)
+{
+ MpegMuxContext *s = ctx->priv_data;
+ int stream_index= pkt->stream_index;
+ int size= pkt->size;
+ uint8_t *buf= pkt->data;
+ AVStream *st = ctx->streams[stream_index];
+ StreamInfo *stream = st->priv_data;
+ int64_t pts, dts;
+ PacketDesc *pkt_desc;
+ const int preload= av_rescale(ctx->preload, 90000, AV_TIME_BASE);
+ const int is_iframe = st->codec->codec_type == CODEC_TYPE_VIDEO && (pkt->flags & PKT_FLAG_KEY);
+
+ pts= pkt->pts;
+ dts= pkt->dts;
+
+ if(pts != AV_NOPTS_VALUE) pts += preload;
+ if(dts != AV_NOPTS_VALUE) dts += preload;
+
+//av_log(ctx, AV_LOG_DEBUG, "dts:%f pts:%f flags:%d stream:%d nopts:%d\n", dts/90000.0, pts/90000.0, pkt->flags, pkt->stream_index, pts != AV_NOPTS_VALUE);
+ if (!stream->premux_packet)
+ stream->next_packet = &stream->premux_packet;
+ *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;
+
+ av_fifo_realloc(&stream->fifo, av_fifo_size(&stream->fifo) + size + 1);
+
+ if (s->is_dvd){
+ if (is_iframe && (s->packet_number == 0 || (pts - stream->vobu_start_pts >= 36000))) { // min VOBU length 0.4 seconds (mpucoder)
+ stream->bytes_to_iframe = av_fifo_size(&stream->fifo);
+ stream->align_iframe = 1;
+ stream->vobu_start_pts = pts;
+ }
+ }
+
+ av_fifo_write(&stream->fifo, buf, size);
+
+ for(;;){
+ int ret= output_packet(ctx, 0);
+ if(ret<=0)
+ return ret;
+ }
+}
+
+static int mpeg_mux_end(AVFormatContext *ctx)
+{
+// MpegMuxContext *s = ctx->priv_data;
+ StreamInfo *stream;
+ int i;
+
+ 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
+ it as it is usually not needed by decoders and because it
+ complicates MPEG stream concatenation. */
+ //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(av_fifo_size(&stream->fifo) == 0);
+ av_fifo_free(&stream->fifo);
+ }
+ return 0;
+}
+
+#ifdef CONFIG_MPEG1SYSTEM_MUXER
+AVOutputFormat mpeg1system_muxer = {
+ "mpeg",
+ "MPEG1 System format",
+ "video/mpeg",
+ "mpg,mpeg",
+ sizeof(MpegMuxContext),
+ CODEC_ID_MP2,
+ CODEC_ID_MPEG1VIDEO,
+ mpeg_mux_init,
+ mpeg_mux_write_packet,
+ mpeg_mux_end,
+};
+#endif
+#ifdef CONFIG_MPEG1VCD_MUXER
+AVOutputFormat mpeg1vcd_muxer = {
+ "vcd",
+ "MPEG1 System format (VCD)",
+ "video/mpeg",
+ NULL,
+ sizeof(MpegMuxContext),
+ CODEC_ID_MP2,
+ CODEC_ID_MPEG1VIDEO,
+ mpeg_mux_init,
+ mpeg_mux_write_packet,
+ mpeg_mux_end,
+};
+#endif
+#ifdef CONFIG_MPEG2VOB_MUXER
+AVOutputFormat mpeg2vob_muxer = {
+ "vob",
+ "MPEG2 PS format (VOB)",
+ "video/mpeg",
+ "vob",
+ sizeof(MpegMuxContext),
+ CODEC_ID_MP2,
+ CODEC_ID_MPEG2VIDEO,
+ mpeg_mux_init,
+ mpeg_mux_write_packet,
+ mpeg_mux_end,
+};
+#endif
+
+/* Same as mpeg2vob_mux except that the pack size is 2324 */
+#ifdef CONFIG_MPEG2SVCD_MUXER
+AVOutputFormat mpeg2svcd_muxer = {
+ "svcd",
+ "MPEG2 PS format (VOB)",
+ "video/mpeg",
+ "vob",
+ sizeof(MpegMuxContext),
+ CODEC_ID_MP2,
+ CODEC_ID_MPEG2VIDEO,
+ mpeg_mux_init,
+ mpeg_mux_write_packet,
+ mpeg_mux_end,
+};
+#endif
+
+/* Same as mpeg2vob_mux except the 'is_dvd' flag is set to produce NAV pkts */
+#ifdef CONFIG_MPEG2DVD_MUXER
+AVOutputFormat mpeg2dvd_muxer = {
+ "dvd",
+ "MPEG2 PS format (DVD VOB)",
+ "video/mpeg",
+ "dvd",
+ sizeof(MpegMuxContext),
+ CODEC_ID_MP2,
+ CODEC_ID_MPEG2VIDEO,
+ mpeg_mux_init,
+ mpeg_mux_write_packet,
+ mpeg_mux_end,
+};
+#endif
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