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 "libavutil/intreadwrite.h"
23 #include "libavutil/intfloat.h"
24 #include "avformat.h"
25 #include "internal.h"
26 #include "ffm.h"
27 
29 {
30  FFMContext *ffm = s->priv_data;
31  int fill_size, h;
32  AVIOContext *pb = s->pb;
33 
34  fill_size = ffm->packet_end - ffm->packet_ptr;
35  memset(ffm->packet_ptr, 0, fill_size);
36 
37  if (avio_tell(pb) % ffm->packet_size)
38  av_abort();
39 
40  /* put header */
41  avio_wb16(pb, PACKET_ID);
42  avio_wb16(pb, fill_size);
43  avio_wb64(pb, ffm->dts);
44  h = ffm->frame_offset;
45  if (ffm->first_packet)
46  h |= 0x8000;
47  avio_wb16(pb, h);
48  avio_write(pb, ffm->packet, ffm->packet_end - ffm->packet);
49  avio_flush(pb);
50 
51  /* prepare next packet */
52  ffm->frame_offset = 0; /* no key frame */
53  ffm->packet_ptr = ffm->packet;
54  ffm->first_packet = 0;
55 }
56 
57 /* 'first' is true if first data of a frame */
59  const uint8_t *buf, int size,
60  int64_t dts, int header)
61 {
62  FFMContext *ffm = s->priv_data;
63  int len;
64 
65  if (header && ffm->frame_offset == 0) {
66  ffm->frame_offset = ffm->packet_ptr - ffm->packet + FFM_HEADER_SIZE;
67  ffm->dts = dts;
68  }
69 
70  /* write as many packets as needed */
71  while (size > 0) {
72  len = ffm->packet_end - ffm->packet_ptr;
73  if (len > size)
74  len = size;
75  memcpy(ffm->packet_ptr, buf, len);
76 
77  ffm->packet_ptr += len;
78  buf += len;
79  size -= len;
80  if (ffm->packet_ptr >= ffm->packet_end)
81  flush_packet(s);
82  }
83 }
84 
86 {
87  FFMContext *ffm = s->priv_data;
88  AVStream *st;
89  AVIOContext *pb = s->pb;
90  AVCodecContext *codec;
91  int bit_rate, i;
92 
94 
95  /* header */
96  avio_wl32(pb, MKTAG('F', 'F', 'M', '1'));
97  avio_wb32(pb, ffm->packet_size);
98  avio_wb64(pb, 0); /* current write position */
99 
100  avio_wb32(pb, s->nb_streams);
101  bit_rate = 0;
102  for(i=0;i<s->nb_streams;i++) {
103  st = s->streams[i];
104  bit_rate += st->codec->bit_rate;
105  }
106  avio_wb32(pb, bit_rate);
107 
108  /* list of streams */
109  for(i=0;i<s->nb_streams;i++) {
110  st = s->streams[i];
111  avpriv_set_pts_info(st, 64, 1, 1000000);
112 
113  codec = st->codec;
114  /* generic info */
115  avio_wb32(pb, codec->codec_id);
116  avio_w8(pb, codec->codec_type);
117  avio_wb32(pb, codec->bit_rate);
118  avio_wb32(pb, codec->flags);
119  avio_wb32(pb, codec->flags2);
120  avio_wb32(pb, codec->debug);
121  /* specific info */
122  switch(codec->codec_type) {
123  case AVMEDIA_TYPE_VIDEO:
124  avio_wb32(pb, codec->time_base.num);
125  avio_wb32(pb, codec->time_base.den);
126  avio_wb16(pb, codec->width);
127  avio_wb16(pb, codec->height);
128  avio_wb16(pb, codec->gop_size);
129  avio_wb32(pb, codec->pix_fmt);
130  avio_w8(pb, codec->qmin);
131  avio_w8(pb, codec->qmax);
132  avio_w8(pb, codec->max_qdiff);
133  avio_wb16(pb, (int) (codec->qcompress * 10000.0));
134  avio_wb16(pb, (int) (codec->qblur * 10000.0));
135  avio_wb32(pb, codec->bit_rate_tolerance);
136  avio_put_str(pb, codec->rc_eq ? codec->rc_eq : "tex^qComp");
137  avio_wb32(pb, codec->rc_max_rate);
138  avio_wb32(pb, codec->rc_min_rate);
139  avio_wb32(pb, codec->rc_buffer_size);
144  avio_wb32(pb, codec->dct_algo);
145  avio_wb32(pb, codec->strict_std_compliance);
146  avio_wb32(pb, codec->max_b_frames);
147  avio_wb32(pb, codec->luma_elim_threshold);
148  avio_wb32(pb, codec->chroma_elim_threshold);
149  avio_wb32(pb, codec->mpeg_quant);
150  avio_wb32(pb, codec->intra_dc_precision);
151  avio_wb32(pb, codec->me_method);
152  avio_wb32(pb, codec->mb_decision);
153  avio_wb32(pb, codec->nsse_weight);
154  avio_wb32(pb, codec->frame_skip_cmp);
156  avio_wb32(pb, codec->codec_tag);
157  avio_w8(pb, codec->thread_count);
158  avio_wb32(pb, codec->coder_type);
159  avio_wb32(pb, codec->me_cmp);
160  avio_wb32(pb, codec->me_subpel_quality);
161  avio_wb32(pb, codec->me_range);
162  avio_wb32(pb, codec->keyint_min);
163  avio_wb32(pb, codec->scenechange_threshold);
164  avio_wb32(pb, codec->b_frame_strategy);
165  avio_wb64(pb, av_double2int(codec->qcompress));
166  avio_wb64(pb, av_double2int(codec->qblur));
167  avio_wb32(pb, codec->max_qdiff);
168  avio_wb32(pb, codec->refs);
169  break;
170  case AVMEDIA_TYPE_AUDIO:
171  avio_wb32(pb, codec->sample_rate);
172  avio_wl16(pb, codec->channels);
173  avio_wl16(pb, codec->frame_size);
174  avio_wl16(pb, codec->sample_fmt);
175  break;
176  default:
177  return -1;
178  }
179  if (codec->flags & CODEC_FLAG_GLOBAL_HEADER) {
180  avio_wb32(pb, codec->extradata_size);
181  avio_write(pb, codec->extradata, codec->extradata_size);
182  }
183  }
184 
185  /* flush until end of block reached */
186  while ((avio_tell(pb) % ffm->packet_size) != 0)
187  avio_w8(pb, 0);
188 
189  avio_flush(pb);
190 
191  /* init packet mux */
192  ffm->packet_ptr = ffm->packet;
193  ffm->packet_end = ffm->packet + ffm->packet_size - FFM_HEADER_SIZE;
194  assert(ffm->packet_end >= ffm->packet);
195  ffm->frame_offset = 0;
196  ffm->dts = 0;
197  ffm->first_packet = 1;
198 
199  return 0;
200 }
201 
203 {
204  int64_t dts;
205  uint8_t header[FRAME_HEADER_SIZE+4];
206  int header_size = FRAME_HEADER_SIZE;
207 
208  dts = pkt->dts;
209  /* packet size & key_frame */
210  header[0] = pkt->stream_index;
211  header[1] = 0;
212  if (pkt->flags & AV_PKT_FLAG_KEY)
213  header[1] |= FLAG_KEY_FRAME;
214  AV_WB24(header+2, pkt->size);
215  AV_WB24(header+5, pkt->duration);
216  AV_WB64(header+8, pkt->pts);
217  if (pkt->pts != pkt->dts) {
218  header[1] |= FLAG_DTS;
219  AV_WB32(header+16, pkt->pts - pkt->dts);
220  header_size += 4;
221  }
222  ffm_write_data(s, header, header_size, dts, 1);
223  ffm_write_data(s, pkt->data, pkt->size, dts, 0);
224 
225  return 0;
226 }
227 
229 {
230  AVIOContext *pb = s->pb;
231  FFMContext *ffm = s->priv_data;
232 
233  /* flush packets */
234  if (ffm->packet_ptr > ffm->packet)
235  flush_packet(s);
236 
237  avio_flush(pb);
238 
239  return 0;
240 }
241 
243  .name = "ffm",
244  .long_name = NULL_IF_CONFIG_SMALL("FFM (AVserver live feed) format"),
245  .mime_type = "",
246  .extensions = "ffm",
247  .priv_data_size = sizeof(FFMContext),
248  .audio_codec = CODEC_ID_MP2,
249  .video_codec = CODEC_ID_MPEG1VIDEO,
253 };