1/* 2 * DXA demuxer 3 * Copyright (c) 2007 Konstantin Shishkov 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 */ 21 22#include "libavutil/intreadwrite.h" 23#include "avformat.h" 24#include "riff.h" 25 26#define DXA_EXTRA_SIZE 9 27 28typedef struct{ 29 int frames; 30 int has_sound; 31 int bpc; 32 uint32_t bytes_left; 33 int64_t wavpos, vidpos; 34 int readvid; 35}DXAContext; 36 37static int dxa_probe(AVProbeData *p) 38{ 39 int w, h; 40 if (p->buf_size < 15) 41 return 0; 42 w = AV_RB16(p->buf + 11); 43 h = AV_RB16(p->buf + 13); 44 /* check file header */ 45 if (p->buf[0] == 'D' && p->buf[1] == 'E' && 46 p->buf[2] == 'X' && p->buf[3] == 'A' && 47 w && w <= 2048 && h && h <= 2048) 48 return AVPROBE_SCORE_MAX; 49 else 50 return 0; 51} 52 53static int dxa_read_header(AVFormatContext *s, AVFormatParameters *ap) 54{ 55 ByteIOContext *pb = s->pb; 56 DXAContext *c = s->priv_data; 57 AVStream *st, *ast; 58 uint32_t tag; 59 int32_t fps; 60 int w, h; 61 int num, den; 62 int flags; 63 64 tag = get_le32(pb); 65 if (tag != MKTAG('D', 'E', 'X', 'A')) 66 return -1; 67 flags = get_byte(pb); 68 c->frames = get_be16(pb); 69 if(!c->frames){ 70 av_log(s, AV_LOG_ERROR, "File contains no frames ???\n"); 71 return -1; 72 } 73 74 fps = get_be32(pb); 75 if(fps > 0){ 76 den = 1000; 77 num = fps; 78 }else if (fps < 0){ 79 den = 100000; 80 num = -fps; 81 }else{ 82 den = 10; 83 num = 1; 84 } 85 w = get_be16(pb); 86 h = get_be16(pb); 87 c->has_sound = 0; 88 89 st = av_new_stream(s, 0); 90 if (!st) 91 return -1; 92 93 // Parse WAV data header 94 if(get_le32(pb) == MKTAG('W', 'A', 'V', 'E')){ 95 uint32_t size, fsize; 96 c->has_sound = 1; 97 size = get_be32(pb); 98 c->vidpos = url_ftell(pb) + size; 99 url_fskip(pb, 16); 100 fsize = get_le32(pb); 101 102 ast = av_new_stream(s, 0); 103 if (!ast) 104 return -1; 105 ff_get_wav_header(pb, ast->codec, fsize); 106 // find 'data' chunk 107 while(url_ftell(pb) < c->vidpos && !url_feof(pb)){ 108 tag = get_le32(pb); 109 fsize = get_le32(pb); 110 if(tag == MKTAG('d', 'a', 't', 'a')) break; 111 url_fskip(pb, fsize); 112 } 113 c->bpc = (fsize + c->frames - 1) / c->frames; 114 if(ast->codec->block_align) 115 c->bpc = ((c->bpc + ast->codec->block_align - 1) / ast->codec->block_align) * ast->codec->block_align; 116 c->bytes_left = fsize; 117 c->wavpos = url_ftell(pb); 118 url_fseek(pb, c->vidpos, SEEK_SET); 119 } 120 121 /* now we are ready: build format streams */ 122 st->codec->codec_type = AVMEDIA_TYPE_VIDEO; 123 st->codec->codec_id = CODEC_ID_DXA; 124 st->codec->width = w; 125 st->codec->height = h; 126 av_reduce(&den, &num, den, num, (1UL<<31)-1); 127 av_set_pts_info(st, 33, num, den); 128 /* flags & 0x80 means that image is interlaced, 129 * flags & 0x40 means that image has double height 130 * either way set true height 131 */ 132 if(flags & 0xC0){ 133 st->codec->height >>= 1; 134 } 135 c->readvid = !c->has_sound; 136 c->vidpos = url_ftell(pb); 137 s->start_time = 0; 138 s->duration = (int64_t)c->frames * AV_TIME_BASE * num / den; 139 av_log(s, AV_LOG_DEBUG, "%d frame(s)\n",c->frames); 140 141 return 0; 142} 143 144static int dxa_read_packet(AVFormatContext *s, AVPacket *pkt) 145{ 146 DXAContext *c = s->priv_data; 147 int ret; 148 uint32_t size; 149 uint8_t buf[DXA_EXTRA_SIZE], pal[768+4]; 150 int pal_size = 0; 151 152 if(!c->readvid && c->has_sound && c->bytes_left){ 153 c->readvid = 1; 154 url_fseek(s->pb, c->wavpos, SEEK_SET); 155 size = FFMIN(c->bytes_left, c->bpc); 156 ret = av_get_packet(s->pb, pkt, size); 157 pkt->stream_index = 1; 158 if(ret != size) 159 return AVERROR(EIO); 160 c->bytes_left -= size; 161 c->wavpos = url_ftell(s->pb); 162 return 0; 163 } 164 url_fseek(s->pb, c->vidpos, SEEK_SET); 165 while(!url_feof(s->pb) && c->frames){ 166 get_buffer(s->pb, buf, 4); 167 switch(AV_RL32(buf)){ 168 case MKTAG('N', 'U', 'L', 'L'): 169 if(av_new_packet(pkt, 4 + pal_size) < 0) 170 return AVERROR(ENOMEM); 171 pkt->stream_index = 0; 172 if(pal_size) memcpy(pkt->data, pal, pal_size); 173 memcpy(pkt->data + pal_size, buf, 4); 174 c->frames--; 175 c->vidpos = url_ftell(s->pb); 176 c->readvid = 0; 177 return 0; 178 case MKTAG('C', 'M', 'A', 'P'): 179 pal_size = 768+4; 180 memcpy(pal, buf, 4); 181 get_buffer(s->pb, pal + 4, 768); 182 break; 183 case MKTAG('F', 'R', 'A', 'M'): 184 get_buffer(s->pb, buf + 4, DXA_EXTRA_SIZE - 4); 185 size = AV_RB32(buf + 5); 186 if(size > 0xFFFFFF){ 187 av_log(s, AV_LOG_ERROR, "Frame size is too big: %d\n", size); 188 return -1; 189 } 190 if(av_new_packet(pkt, size + DXA_EXTRA_SIZE + pal_size) < 0) 191 return AVERROR(ENOMEM); 192 memcpy(pkt->data + pal_size, buf, DXA_EXTRA_SIZE); 193 ret = get_buffer(s->pb, pkt->data + DXA_EXTRA_SIZE + pal_size, size); 194 if(ret != size){ 195 av_free_packet(pkt); 196 return AVERROR(EIO); 197 } 198 if(pal_size) memcpy(pkt->data, pal, pal_size); 199 pkt->stream_index = 0; 200 c->frames--; 201 c->vidpos = url_ftell(s->pb); 202 c->readvid = 0; 203 return 0; 204 default: 205 av_log(s, AV_LOG_ERROR, "Unknown tag %c%c%c%c\n", buf[0], buf[1], buf[2], buf[3]); 206 return -1; 207 } 208 } 209 return AVERROR(EIO); 210} 211 212AVInputFormat dxa_demuxer = { 213 "dxa", 214 NULL_IF_CONFIG_SMALL("DXA"), 215 sizeof(DXAContext), 216 dxa_probe, 217 dxa_read_header, 218 dxa_read_packet, 219}; 220