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00023 #include "libavutil/intreadwrite.h"
00024 #include "swf.h"
00025
00026 static int get_swf_tag(AVIOContext *pb, int *len_ptr)
00027 {
00028 int tag, len;
00029
00030 if (url_feof(pb))
00031 return -1;
00032
00033 tag = avio_rl16(pb);
00034 len = tag & 0x3f;
00035 tag = tag >> 6;
00036 if (len == 0x3f) {
00037 len = avio_rl32(pb);
00038 }
00039
00040 *len_ptr = len;
00041 return tag;
00042 }
00043
00044
00045 static int swf_probe(AVProbeData *p)
00046 {
00047
00048 if ((p->buf[0] == 'F' || p->buf[0] == 'C') && p->buf[1] == 'W' &&
00049 p->buf[2] == 'S')
00050 return AVPROBE_SCORE_MAX;
00051 else
00052 return 0;
00053 }
00054
00055 static int swf_read_header(AVFormatContext *s, AVFormatParameters *ap)
00056 {
00057 SWFContext *swf = s->priv_data;
00058 AVIOContext *pb = s->pb;
00059 int nbits, len, tag;
00060
00061 tag = avio_rb32(pb) & 0xffffff00;
00062
00063 if (tag == MKBETAG('C', 'W', 'S', 0)) {
00064 av_log(s, AV_LOG_ERROR, "Compressed SWF format not supported\n");
00065 return AVERROR(EIO);
00066 }
00067 if (tag != MKBETAG('F', 'W', 'S', 0))
00068 return AVERROR(EIO);
00069 avio_rl32(pb);
00070
00071 nbits = avio_r8(pb) >> 3;
00072 len = (4 * nbits - 3 + 7) / 8;
00073 avio_skip(pb, len);
00074 swf->frame_rate = avio_rl16(pb);
00075 avio_rl16(pb);
00076
00077 swf->samples_per_frame = 0;
00078 s->ctx_flags |= AVFMTCTX_NOHEADER;
00079 return 0;
00080 }
00081
00082 static int swf_read_packet(AVFormatContext *s, AVPacket *pkt)
00083 {
00084 SWFContext *swf = s->priv_data;
00085 AVIOContext *pb = s->pb;
00086 AVStream *vst = NULL, *ast = NULL, *st = 0;
00087 int tag, len, i, frame, v, res;
00088
00089 for(;;) {
00090 uint64_t pos = avio_tell(pb);
00091 tag = get_swf_tag(pb, &len);
00092 if (tag < 0)
00093 return AVERROR(EIO);
00094 if (tag == TAG_VIDEOSTREAM) {
00095 int ch_id = avio_rl16(pb);
00096 len -= 2;
00097
00098 for (i=0; i<s->nb_streams; i++) {
00099 st = s->streams[i];
00100 if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO && st->id == ch_id)
00101 goto skip;
00102 }
00103
00104 avio_rl16(pb);
00105 avio_rl16(pb);
00106 avio_rl16(pb);
00107 avio_r8(pb);
00108
00109 vst = av_new_stream(s, ch_id);
00110 if (!vst)
00111 return -1;
00112 vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
00113 vst->codec->codec_id = ff_codec_get_id(swf_codec_tags, avio_r8(pb));
00114 av_set_pts_info(vst, 16, 256, swf->frame_rate);
00115 vst->codec->time_base = (AVRational){ 256, swf->frame_rate };
00116 len -= 8;
00117 } else if (tag == TAG_STREAMHEAD || tag == TAG_STREAMHEAD2) {
00118
00119 int sample_rate_code;
00120
00121 for (i=0; i<s->nb_streams; i++) {
00122 st = s->streams[i];
00123 if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO && st->id == -1)
00124 goto skip;
00125 }
00126
00127 avio_r8(pb);
00128 v = avio_r8(pb);
00129 swf->samples_per_frame = avio_rl16(pb);
00130 ast = av_new_stream(s, -1);
00131 if (!ast)
00132 return -1;
00133 ast->codec->channels = 1 + (v&1);
00134 ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00135 ast->codec->codec_id = ff_codec_get_id(swf_audio_codec_tags, (v>>4) & 15);
00136 ast->need_parsing = AVSTREAM_PARSE_FULL;
00137 sample_rate_code= (v>>2) & 3;
00138 if (!sample_rate_code)
00139 return AVERROR(EIO);
00140 ast->codec->sample_rate = 11025 << (sample_rate_code-1);
00141 av_set_pts_info(ast, 64, 1, ast->codec->sample_rate);
00142 len -= 4;
00143 } else if (tag == TAG_VIDEOFRAME) {
00144 int ch_id = avio_rl16(pb);
00145 len -= 2;
00146 for(i=0; i<s->nb_streams; i++) {
00147 st = s->streams[i];
00148 if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO && st->id == ch_id) {
00149 frame = avio_rl16(pb);
00150 if ((res = av_get_packet(pb, pkt, len-2)) < 0)
00151 return res;
00152 pkt->pos = pos;
00153 pkt->pts = frame;
00154 pkt->stream_index = st->index;
00155 return pkt->size;
00156 }
00157 }
00158 } else if (tag == TAG_STREAMBLOCK) {
00159 for (i = 0; i < s->nb_streams; i++) {
00160 st = s->streams[i];
00161 if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO && st->id == -1) {
00162 if (st->codec->codec_id == CODEC_ID_MP3) {
00163 avio_skip(pb, 4);
00164 if ((res = av_get_packet(pb, pkt, len-4)) < 0)
00165 return res;
00166 } else {
00167 if ((res = av_get_packet(pb, pkt, len)) < 0)
00168 return res;
00169 }
00170 pkt->pos = pos;
00171 pkt->stream_index = st->index;
00172 return pkt->size;
00173 }
00174 }
00175 } else if (tag == TAG_JPEG2) {
00176 for (i=0; i<s->nb_streams; i++) {
00177 st = s->streams[i];
00178 if (st->codec->codec_id == CODEC_ID_MJPEG && st->id == -2)
00179 break;
00180 }
00181 if (i == s->nb_streams) {
00182 vst = av_new_stream(s, -2);
00183 if (!vst)
00184 return -1;
00185 vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
00186 vst->codec->codec_id = CODEC_ID_MJPEG;
00187 av_set_pts_info(vst, 64, 256, swf->frame_rate);
00188 vst->codec->time_base = (AVRational){ 256, swf->frame_rate };
00189 st = vst;
00190 }
00191 avio_rl16(pb);
00192 if ((res = av_new_packet(pkt, len-2)) < 0)
00193 return res;
00194 avio_read(pb, pkt->data, 4);
00195 if (AV_RB32(pkt->data) == 0xffd8ffd9 ||
00196 AV_RB32(pkt->data) == 0xffd9ffd8) {
00197
00198
00199 pkt->size -= 4;
00200 avio_read(pb, pkt->data, pkt->size);
00201 } else {
00202 avio_read(pb, pkt->data + 4, pkt->size - 4);
00203 }
00204 pkt->pos = pos;
00205 pkt->stream_index = st->index;
00206 return pkt->size;
00207 }
00208 skip:
00209 avio_skip(pb, len);
00210 }
00211 return 0;
00212 }
00213
00214 AVInputFormat ff_swf_demuxer = {
00215 "swf",
00216 NULL_IF_CONFIG_SMALL("Flash format"),
00217 sizeof(SWFContext),
00218 swf_probe,
00219 swf_read_header,
00220 swf_read_packet,
00221 };