FFmpeg: libavformat/ffmenc.c Source File

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libavformat

ffmenc.c

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1 /*

2 * FFM (ffserver live feed) muxer

4 *

5 * This file is part of FFmpeg.

6 *

7 * FFmpeg 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 * FFmpeg 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 FFmpeg; if not, write to the Free Software

19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

20 */

22 #include "libavutil/intreadwrite.h"

23 #include "libavutil/intfloat.h"

24 #include "libavutil/avassert.h"

25 #include "libavutil/parseutils.h"

26 #include "avformat.h"

27 #include "internal.h"

28 #include "ffm.h"

30 static void flush_packet(AVFormatContext *s)

31 {

32 FFMContext *ffm = s->priv_data;

33 int fill_size, h;

34 AVIOContext *pb = s->pb;

36 fill_size = ffm->packet_end - ffm->packet_ptr;

37 memset(ffm->packet_ptr, 0, fill_size);

39 av_assert1(avio_tell(pb) % ffm->packet_size == 0);

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);

52 /* prepare next packet */

53 ffm->frame_offset = 0; /* no key frame */

54 ffm->packet_ptr = ffm->packet;

55 ffm->first_packet = 0;

56 }

58 /* 'first' is true if first data of a frame */

59 static void ffm_write_data(AVFormatContext *s,

60 const uint8_t *buf, int size,

61 int64_t dts, int header)

62 {

63 FFMContext *ffm = s->priv_data;

64 int len;

66 if (header && ffm->frame_offset == 0) {

67 ffm->frame_offset = ffm->packet_ptr - ffm->packet + FFM_HEADER_SIZE;

68 ffm->dts = dts;

69 }

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);

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 }

86 static void write_header_chunk(AVIOContext *pb, AVIOContext *dpb, unsigned id)

87 {

88 uint8_t *dyn_buf;

89 int dyn_size= avio_close_dyn_buf(dpb, &dyn_buf);

90 avio_wb32(pb, id);

91 avio_wb32(pb, dyn_size);

92 avio_write(pb, dyn_buf, dyn_size);

93 av_free(dyn_buf);

94 }

96 static int ffm_write_header(AVFormatContext *s)

97 {

98 FFMContext *ffm = s->priv_data;

99 AVDictionaryEntry *t;

100 AVStream *st;

101 AVIOContext *pb = s->pb;

102 AVCodecContext *codec;

103 int bit_rate, i;

104

105 if (t = av_dict_get(s->metadata, "creation_time", NULL, 0)) {

106 int ret = av_parse_time(&ffm->start_time, t->value, 0);

107 if (ret < 0)

108 return ret;

109 }

110

111 ffm->packet_size = FFM_PACKET_SIZE;

112

113 /* header */

114 avio_wl32(pb, MKTAG('F', 'F', 'M', '2'));

115 avio_wb32(pb, ffm->packet_size);

116 avio_wb64(pb, 0); /* current write position */

117

118 if(avio_open_dyn_buf(&pb) < 0)

119 return AVERROR(ENOMEM);

120

121 avio_wb32(pb, s->nb_streams);

122 bit_rate = 0;

123 for(i=0;i<s->nb_streams;i++) {

124 st = s->streams[i];

125 bit_rate += st->codec->bit_rate;

126 }

127 avio_wb32(pb, bit_rate);

128

129 write_header_chunk(s->pb, pb, MKBETAG('M', 'A', 'I', 'N'));

130

131 /* list of streams */

132 for(i=0;i<s->nb_streams;i++) {

133 st = s->streams[i];

134 avpriv_set_pts_info(st, 64, 1, 1000000);

135 if(avio_open_dyn_buf(&pb) < 0)

136 return AVERROR(ENOMEM);

137

138 codec = st->codec;

139 /* generic info */

140 avio_wb32(pb, codec->codec_id);

141 avio_w8(pb, codec->codec_type);

142 avio_wb32(pb, codec->bit_rate);

143 avio_wb32(pb, codec->flags);

144 avio_wb32(pb, codec->flags2);

145 avio_wb32(pb, codec->debug);

146 if (codec->flags & CODEC_FLAG_GLOBAL_HEADER) {

147 avio_wb32(pb, codec->extradata_size);

148 avio_write(pb, codec->extradata, codec->extradata_size);

149 }

150 write_header_chunk(s->pb, pb, MKBETAG('C', 'O', 'M', 'M'));

151 if(avio_open_dyn_buf(&pb) < 0)

152 return AVERROR(ENOMEM);

153 /* specific info */

154 switch(codec->codec_type) {

155 case AVMEDIA_TYPE_VIDEO:

156 avio_wb32(pb, codec->time_base.num);

157 avio_wb32(pb, codec->time_base.den);

158 avio_wb16(pb, codec->width);

159 avio_wb16(pb, codec->height);

160 avio_wb16(pb, codec->gop_size);

161 avio_wb32(pb, codec->pix_fmt);

162 avio_w8(pb, codec->qmin);

163 avio_w8(pb, codec->qmax);

164 avio_w8(pb, codec->max_qdiff);

165 avio_wb16(pb, (int) (codec->qcompress * 10000.0));

166 avio_wb16(pb, (int) (codec->qblur * 10000.0));

167 avio_wb32(pb, codec->bit_rate_tolerance);

168 avio_put_str(pb, codec->rc_eq ? codec->rc_eq : "tex^qComp");

169 avio_wb32(pb, codec->rc_max_rate);

170 avio_wb32(pb, codec->rc_min_rate);

171 avio_wb32(pb, codec->rc_buffer_size);

172 avio_wb64(pb, av_double2int(codec->i_quant_factor));

173 avio_wb64(pb, av_double2int(codec->b_quant_factor));

174 avio_wb64(pb, av_double2int(codec->i_quant_offset));

175 avio_wb64(pb, av_double2int(codec->b_quant_offset));

176 avio_wb32(pb, codec->dct_algo);

177 avio_wb32(pb, codec->strict_std_compliance);

178 avio_wb32(pb, codec->max_b_frames);

179 avio_wb32(pb, codec->mpeg_quant);

180 avio_wb32(pb, codec->intra_dc_precision);

181 avio_wb32(pb, codec->me_method);

182 avio_wb32(pb, codec->mb_decision);

183 avio_wb32(pb, codec->nsse_weight);

184 avio_wb32(pb, codec->frame_skip_cmp);

185 avio_wb64(pb, av_double2int(codec->rc_buffer_aggressivity));

186 avio_wb32(pb, codec->codec_tag);

187 avio_w8(pb, codec->thread_count);

188 avio_wb32(pb, codec->coder_type);

189 avio_wb32(pb, codec->me_cmp);

190 avio_wb32(pb, codec->me_subpel_quality);

191 avio_wb32(pb, codec->me_range);

192 avio_wb32(pb, codec->keyint_min);

193 avio_wb32(pb, codec->scenechange_threshold);

194 avio_wb32(pb, codec->b_frame_strategy);

195 avio_wb64(pb, av_double2int(codec->qcompress));

196 avio_wb64(pb, av_double2int(codec->qblur));

197 avio_wb32(pb, codec->max_qdiff);

198 avio_wb32(pb, codec->refs);

199 write_header_chunk(s->pb, pb, MKBETAG('S', 'T', 'V', 'I'));

200 break;

201 case AVMEDIA_TYPE_AUDIO:

202 avio_wb32(pb, codec->sample_rate);

203 avio_wl16(pb, codec->channels);

204 avio_wl16(pb, codec->frame_size);

205 write_header_chunk(s->pb, pb, MKBETAG('S', 'T', 'A', 'U'));

206 break;

207 default:

208 return -1;

209 }

210 }

211 pb = s->pb;

212

213 avio_wb64(pb, 0); // end of header

214

215 /* flush until end of block reached */

216 while ((avio_tell(pb) % ffm->packet_size) != 0)

217 avio_w8(pb, 0);

218

219 avio_flush(pb);

220

221 /* init packet mux */

222 ffm->packet_ptr = ffm->packet;

223 ffm->packet_end = ffm->packet + ffm->packet_size - FFM_HEADER_SIZE;

224 av_assert0(ffm->packet_end >= ffm->packet);

225 ffm->frame_offset = 0;

226 ffm->dts = 0;

227 ffm->first_packet = 1;

228

229 return 0;

230 }

231

232 static int ffm_write_packet(AVFormatContext *s, AVPacket *pkt)

233 {

234 FFMContext *ffm = s->priv_data;

235 int64_t dts;

236 uint8_t header[FRAME_HEADER_SIZE+4];

237 int header_size = FRAME_HEADER_SIZE;

238

239 dts = ffm->start_time + pkt->dts;

240 /* packet size & key_frame */

241 header[0] = pkt->stream_index;

242 header[1] = 0;

243 if (pkt->flags & AV_PKT_FLAG_KEY)

244 header[1] |= FLAG_KEY_FRAME;

245 AV_WB24(header+2, pkt->size);

246 AV_WB24(header+5, pkt->duration);

247 AV_WB64(header+8, ffm->start_time + pkt->pts);

248 if (pkt->pts != pkt->dts) {

249 header[1] |= FLAG_DTS;

250 AV_WB32(header+16, pkt->pts - pkt->dts);

251 header_size += 4;

252 }

253 ffm_write_data(s, header, header_size, dts, 1);

254 ffm_write_data(s, pkt->data, pkt->size, dts, 0);

255

256 return 0;

257 }

258

259 static int ffm_write_trailer(AVFormatContext *s)

260 {

261 FFMContext *ffm = s->priv_data;

262

263 /* flush packets */

264 if (ffm->packet_ptr > ffm->packet)

265 flush_packet(s);

266

267 return 0;

268 }

269

270 AVOutputFormat ff_ffm_muxer = {

271 .name = "ffm",

272 .long_name = NULL_IF_CONFIG_SMALL("FFM (FFserver live feed)"),

273 .extensions = "ffm",

274 .priv_data_size = sizeof(FFMContext),

275 .audio_codec = AV_CODEC_ID_MP2,

276 .video_codec = AV_CODEC_ID_MPEG1VIDEO,

277 .write_header = ffm_write_header,

278 .write_packet = ffm_write_packet,

279 .write_trailer = ffm_write_trailer,

280 .flags = AVFMT_TS_NEGATIVE,

281 };

Generated on Wed Jul 10 2013 23:48:12 for FFmpeg by doxygen 1.8.2