1/* 2 * Flash Compatible Streaming Format demuxer 3 * Copyright (c) 2000 Fabrice Bellard 4 * Copyright (c) 2003 Tinic Uro 5 * 6 * This file is part of Libav. 7 * 8 * Libav is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU Lesser General Public 10 * License as published by the Free Software Foundation; either 11 * version 2.1 of the License, or (at your option) any later version. 12 * 13 * Libav is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * Lesser General Public License for more details. 17 * 18 * You should have received a copy of the GNU Lesser General Public 19 * License along with Libav; if not, write to the Free Software 20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 21 */ 22 23#include "libavutil/intreadwrite.h" 24#include "swf.h" 25 26static int get_swf_tag(AVIOContext *pb, int *len_ptr) 27{ 28 int tag, len; 29 30 if (pb->eof_reached) 31 return -1; 32 33 tag = avio_rl16(pb); 34 len = tag & 0x3f; 35 tag = tag >> 6; 36 if (len == 0x3f) { 37 len = avio_rl32(pb); 38 } 39// av_log(NULL, AV_LOG_DEBUG, "Tag: %d - Len: %d\n", tag, len); 40 *len_ptr = len; 41 return tag; 42} 43 44 45static int swf_probe(AVProbeData *p) 46{ 47 /* check file header */ 48 if ((p->buf[0] == 'F' || p->buf[0] == 'C') && p->buf[1] == 'W' && 49 p->buf[2] == 'S') 50 return AVPROBE_SCORE_MAX; 51 else 52 return 0; 53} 54 55static int swf_read_header(AVFormatContext *s, AVFormatParameters *ap) 56{ 57 SWFContext *swf = s->priv_data; 58 AVIOContext *pb = s->pb; 59 int nbits, len, tag; 60 61 tag = avio_rb32(pb) & 0xffffff00; 62 63 if (tag == MKBETAG('C', 'W', 'S', 0)) { 64 av_log(s, AV_LOG_ERROR, "Compressed SWF format not supported\n"); 65 return AVERROR(EIO); 66 } 67 if (tag != MKBETAG('F', 'W', 'S', 0)) 68 return AVERROR(EIO); 69 avio_rl32(pb); 70 /* skip rectangle size */ 71 nbits = avio_r8(pb) >> 3; 72 len = (4 * nbits - 3 + 7) / 8; 73 avio_skip(pb, len); 74 swf->frame_rate = avio_rl16(pb); /* 8.8 fixed */ 75 avio_rl16(pb); /* frame count */ 76 77 swf->samples_per_frame = 0; 78 s->ctx_flags |= AVFMTCTX_NOHEADER; 79 return 0; 80} 81 82static int swf_read_packet(AVFormatContext *s, AVPacket *pkt) 83{ 84 SWFContext *swf = s->priv_data; 85 AVIOContext *pb = s->pb; 86 AVStream *vst = NULL, *ast = NULL, *st = 0; 87 int tag, len, i, frame, v, res; 88 89 for(;;) { 90 uint64_t pos = avio_tell(pb); 91 tag = get_swf_tag(pb, &len); 92 if (tag < 0) 93 return AVERROR(EIO); 94 if (tag == TAG_VIDEOSTREAM) { 95 int ch_id = avio_rl16(pb); 96 len -= 2; 97 98 for (i=0; i<s->nb_streams; i++) { 99 st = s->streams[i]; 100 if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO && st->id == ch_id) 101 goto skip; 102 } 103 104 avio_rl16(pb); 105 avio_rl16(pb); 106 avio_rl16(pb); 107 avio_r8(pb); 108 /* Check for FLV1 */ 109 vst = avformat_new_stream(s, NULL); 110 if (!vst) 111 return -1; 112 vst->id = ch_id; 113 vst->codec->codec_type = AVMEDIA_TYPE_VIDEO; 114 vst->codec->codec_id = ff_codec_get_id(swf_codec_tags, avio_r8(pb)); 115 avpriv_set_pts_info(vst, 16, 256, swf->frame_rate); 116 vst->codec->time_base = (AVRational){ 256, swf->frame_rate }; 117 len -= 8; 118 } else if (tag == TAG_STREAMHEAD || tag == TAG_STREAMHEAD2) { 119 /* streaming found */ 120 int sample_rate_code; 121 122 for (i=0; i<s->nb_streams; i++) { 123 st = s->streams[i]; 124 if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO && st->id == -1) 125 goto skip; 126 } 127 128 avio_r8(pb); 129 v = avio_r8(pb); 130 swf->samples_per_frame = avio_rl16(pb); 131 ast = avformat_new_stream(s, NULL); 132 if (!ast) 133 return -1; 134 ast->id = -1; /* -1 to avoid clash with video stream ch_id */ 135 ast->codec->channels = 1 + (v&1); 136 ast->codec->codec_type = AVMEDIA_TYPE_AUDIO; 137 ast->codec->codec_id = ff_codec_get_id(swf_audio_codec_tags, (v>>4) & 15); 138 ast->need_parsing = AVSTREAM_PARSE_FULL; 139 sample_rate_code= (v>>2) & 3; 140 if (!sample_rate_code) 141 ast->codec->sample_rate = 5512; 142 else 143 ast->codec->sample_rate = 11025 << (sample_rate_code-1); 144 avpriv_set_pts_info(ast, 64, 1, ast->codec->sample_rate); 145 len -= 4; 146 } else if (tag == TAG_VIDEOFRAME) { 147 int ch_id = avio_rl16(pb); 148 len -= 2; 149 for(i=0; i<s->nb_streams; i++) { 150 st = s->streams[i]; 151 if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO && st->id == ch_id) { 152 frame = avio_rl16(pb); 153 if ((res = av_get_packet(pb, pkt, len-2)) < 0) 154 return res; 155 pkt->pos = pos; 156 pkt->pts = frame; 157 pkt->stream_index = st->index; 158 return pkt->size; 159 } 160 } 161 } else if (tag == TAG_STREAMBLOCK) { 162 for (i = 0; i < s->nb_streams; i++) { 163 st = s->streams[i]; 164 if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO && st->id == -1) { 165 if (st->codec->codec_id == CODEC_ID_MP3) { 166 avio_skip(pb, 4); 167 if ((res = av_get_packet(pb, pkt, len-4)) < 0) 168 return res; 169 } else { // ADPCM, PCM 170 if ((res = av_get_packet(pb, pkt, len)) < 0) 171 return res; 172 } 173 pkt->pos = pos; 174 pkt->stream_index = st->index; 175 return pkt->size; 176 } 177 } 178 } else if (tag == TAG_JPEG2) { 179 for (i=0; i<s->nb_streams; i++) { 180 st = s->streams[i]; 181 if (st->codec->codec_id == CODEC_ID_MJPEG && st->id == -2) 182 break; 183 } 184 if (i == s->nb_streams) { 185 vst = avformat_new_stream(s, NULL); 186 if (!vst) 187 return -1; 188 vst->id = -2; /* -2 to avoid clash with video stream and audio stream */ 189 vst->codec->codec_type = AVMEDIA_TYPE_VIDEO; 190 vst->codec->codec_id = CODEC_ID_MJPEG; 191 avpriv_set_pts_info(vst, 64, 256, swf->frame_rate); 192 vst->codec->time_base = (AVRational){ 256, swf->frame_rate }; 193 st = vst; 194 } 195 avio_rl16(pb); /* BITMAP_ID */ 196 if ((res = av_new_packet(pkt, len-2)) < 0) 197 return res; 198 avio_read(pb, pkt->data, 4); 199 if (AV_RB32(pkt->data) == 0xffd8ffd9 || 200 AV_RB32(pkt->data) == 0xffd9ffd8) { 201 /* old SWF files containing SOI/EOI as data start */ 202 /* files created by swink have reversed tag */ 203 pkt->size -= 4; 204 avio_read(pb, pkt->data, pkt->size); 205 } else { 206 avio_read(pb, pkt->data + 4, pkt->size - 4); 207 } 208 pkt->pos = pos; 209 pkt->stream_index = st->index; 210 return pkt->size; 211 } 212 skip: 213 avio_skip(pb, len); 214 } 215} 216 217AVInputFormat ff_swf_demuxer = { 218 .name = "swf", 219 .long_name = NULL_IF_CONFIG_SMALL("Flash format"), 220 .priv_data_size = sizeof(SWFContext), 221 .read_probe = swf_probe, 222 .read_header = swf_read_header, 223 .read_packet = swf_read_packet, 224}; 225