Libav
ffmenc.c
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1 /*
2  * FFM (avserver live feed) muxer
3  * Copyright (c) 2001 Fabrice Bellard
4  *
5  * This file is part of Libav.
6  *
7  * Libav is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * Libav is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include <assert.h>
23 
24 #include "libavutil/intreadwrite.h"
25 #include "libavutil/intfloat.h"
26 #include "avformat.h"
27 #include "internal.h"
28 #include "ffm.h"
29 
31 {
32  FFMContext *ffm = s->priv_data;
33  int fill_size, h;
34  AVIOContext *pb = s->pb;
35 
36  fill_size = ffm->packet_end - ffm->packet_ptr;
37  memset(ffm->packet_ptr, 0, fill_size);
38 
39  assert(avio_tell(pb) % ffm->packet_size == 0);
40 
41  /* put header */
42  avio_wb16(pb, PACKET_ID);
43  avio_wb16(pb, fill_size);
44  avio_wb64(pb, ffm->dts);
45  h = ffm->frame_offset;
46  if (ffm->first_packet)
47  h |= 0x8000;
48  avio_wb16(pb, h);
49  avio_write(pb, ffm->packet, ffm->packet_end - ffm->packet);
50  avio_flush(pb);
51 
52  /* prepare next packet */
53  ffm->frame_offset = 0; /* no key frame */
54  ffm->packet_ptr = ffm->packet;
55  ffm->first_packet = 0;
56 }
57 
58 /* 'first' is true if first data of a frame */
60  const uint8_t *buf, int size,
61  int64_t dts, int header)
62 {
63  FFMContext *ffm = s->priv_data;
64  int len;
65 
66  if (header && ffm->frame_offset == 0) {
67  ffm->frame_offset = ffm->packet_ptr - ffm->packet + FFM_HEADER_SIZE;
68  ffm->dts = dts;
69  }
70 
71  /* write as many packets as needed */
72  while (size > 0) {
73  len = ffm->packet_end - ffm->packet_ptr;
74  if (len > size)
75  len = size;
76  memcpy(ffm->packet_ptr, buf, len);
77 
78  ffm->packet_ptr += len;
79  buf += len;
80  size -= len;
81  if (ffm->packet_ptr >= ffm->packet_end)
82  flush_packet(s);
83  }
84 }
85 
87 {
88  FFMContext *ffm = s->priv_data;
89  AVStream *st;
90  AVIOContext *pb = s->pb;
91  AVCodecContext *codec;
92  int bit_rate, i;
93 
95 
96  /* header */
97  avio_wl32(pb, MKTAG('F', 'F', 'M', '1'));
98  avio_wb32(pb, ffm->packet_size);
99  avio_wb64(pb, 0); /* current write position */
100 
101  avio_wb32(pb, s->nb_streams);
102  bit_rate = 0;
103  for(i=0;i<s->nb_streams;i++) {
104  st = s->streams[i];
105  bit_rate += st->codec->bit_rate;
106  }
107  avio_wb32(pb, bit_rate);
108 
109  /* list of streams */
110  for(i=0;i<s->nb_streams;i++) {
111  st = s->streams[i];
112  avpriv_set_pts_info(st, 64, 1, 1000000);
113 
114  codec = st->codec;
115  /* generic info */
116  avio_wb32(pb, codec->codec_id);
117  avio_w8(pb, codec->codec_type);
118  avio_wb32(pb, codec->bit_rate);
119  avio_wb32(pb, codec->flags);
120  avio_wb32(pb, codec->flags2);
121  avio_wb32(pb, codec->debug);
122  /* specific info */
123  switch(codec->codec_type) {
124  case AVMEDIA_TYPE_VIDEO:
125  avio_wb32(pb, codec->time_base.num);
126  avio_wb32(pb, codec->time_base.den);
127  avio_wb16(pb, codec->width);
128  avio_wb16(pb, codec->height);
129  avio_wb16(pb, codec->gop_size);
130  avio_wb32(pb, codec->pix_fmt);
131  avio_w8(pb, codec->qmin);
132  avio_w8(pb, codec->qmax);
133  avio_w8(pb, codec->max_qdiff);
134  avio_wb16(pb, (int) (codec->qcompress * 10000.0));
135  avio_wb16(pb, (int) (codec->qblur * 10000.0));
136  avio_wb32(pb, codec->bit_rate_tolerance);
137  avio_put_str(pb, codec->rc_eq ? codec->rc_eq : "tex^qComp");
138  avio_wb32(pb, codec->rc_max_rate);
139  avio_wb32(pb, codec->rc_min_rate);
140  avio_wb32(pb, codec->rc_buffer_size);
145  avio_wb32(pb, codec->dct_algo);
146  avio_wb32(pb, codec->strict_std_compliance);
147  avio_wb32(pb, codec->max_b_frames);
148  avio_wb32(pb, codec->mpeg_quant);
149  avio_wb32(pb, codec->intra_dc_precision);
150  avio_wb32(pb, codec->me_method);
151  avio_wb32(pb, codec->mb_decision);
152  avio_wb32(pb, codec->nsse_weight);
153  avio_wb32(pb, codec->frame_skip_cmp);
155  avio_wb32(pb, codec->codec_tag);
156  avio_w8(pb, codec->thread_count);
157  avio_wb32(pb, codec->coder_type);
158  avio_wb32(pb, codec->me_cmp);
159  avio_wb32(pb, codec->me_subpel_quality);
160  avio_wb32(pb, codec->me_range);
161  avio_wb32(pb, codec->keyint_min);
162  avio_wb32(pb, codec->scenechange_threshold);
163  avio_wb32(pb, codec->b_frame_strategy);
164  avio_wb64(pb, av_double2int(codec->qcompress));
165  avio_wb64(pb, av_double2int(codec->qblur));
166  avio_wb32(pb, codec->max_qdiff);
167  avio_wb32(pb, codec->refs);
168  break;
169  case AVMEDIA_TYPE_AUDIO:
170  avio_wb32(pb, codec->sample_rate);
171  avio_wl16(pb, codec->channels);
172  avio_wl16(pb, codec->frame_size);
173  break;
174  default:
175  return -1;
176  }
177  if (codec->flags & CODEC_FLAG_GLOBAL_HEADER) {
178  avio_wb32(pb, codec->extradata_size);
179  avio_write(pb, codec->extradata, codec->extradata_size);
180  }
181  }
182 
183  /* flush until end of block reached */
184  while ((avio_tell(pb) % ffm->packet_size) != 0)
185  avio_w8(pb, 0);
186 
187  avio_flush(pb);
188 
189  /* init packet mux */
190  ffm->packet_ptr = ffm->packet;
191  ffm->packet_end = ffm->packet + ffm->packet_size - FFM_HEADER_SIZE;
192  assert(ffm->packet_end >= ffm->packet);
193  ffm->frame_offset = 0;
194  ffm->dts = 0;
195  ffm->first_packet = 1;
196 
197  return 0;
198 }
199 
201 {
202  int64_t dts;
203  uint8_t header[FRAME_HEADER_SIZE+4];
204  int header_size = FRAME_HEADER_SIZE;
205 
206  dts = pkt->dts;
207  /* packet size & key_frame */
208  header[0] = pkt->stream_index;
209  header[1] = 0;
210  if (pkt->flags & AV_PKT_FLAG_KEY)
211  header[1] |= FLAG_KEY_FRAME;
212  AV_WB24(header+2, pkt->size);
213  AV_WB24(header+5, pkt->duration);
214  AV_WB64(header+8, pkt->pts);
215  if (pkt->pts != pkt->dts) {
216  header[1] |= FLAG_DTS;
217  AV_WB32(header+16, pkt->pts - pkt->dts);
218  header_size += 4;
219  }
220  ffm_write_data(s, header, header_size, dts, 1);
221  ffm_write_data(s, pkt->data, pkt->size, dts, 0);
222 
223  return 0;
224 }
225 
227 {
228  FFMContext *ffm = s->priv_data;
229 
230  /* flush packets */
231  if (ffm->packet_ptr > ffm->packet)
232  flush_packet(s);
233 
234  return 0;
235 }
236 
238  .name = "ffm",
239  .long_name = NULL_IF_CONFIG_SMALL("FFM (AVserver live feed)"),
240  .mime_type = "",
241  .extensions = "ffm",
242  .priv_data_size = sizeof(FFMContext),
243  .audio_codec = AV_CODEC_ID_MP2,
244  .video_codec = AV_CODEC_ID_MPEG1VIDEO,
249 };