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libavformat/rpl.c

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00001 /*
00002  * ARMovie/RPL demuxer
00003  * Copyright (c) 2007 Christian Ohm, 2008 Eli Friedman
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00022 #include "libavutil/avstring.h"
00023 #include "avformat.h"
00024 #include <stdlib.h>
00025 
00026 #define RPL_SIGNATURE "ARMovie\x0A"
00027 #define RPL_SIGNATURE_SIZE 8
00028 
00030 #define RPL_LINE_LENGTH 256
00031 
00032 static int rpl_probe(AVProbeData *p)
00033 {
00034     if (memcmp(p->buf, RPL_SIGNATURE, RPL_SIGNATURE_SIZE))
00035         return 0;
00036 
00037     return AVPROBE_SCORE_MAX;
00038 }
00039 
00040 typedef struct RPLContext {
00041     // RPL header data
00042     int32_t frames_per_chunk;
00043 
00044     // Stream position data
00045     uint32_t chunk_number;
00046     uint32_t chunk_part;
00047     uint32_t frame_in_part;
00048 } RPLContext;
00049 
00050 static int read_line(ByteIOContext * pb, char* line, int bufsize)
00051 {
00052     int i;
00053     for (i = 0; i < bufsize - 1; i++) {
00054         int b = get_byte(pb);
00055         if (b == 0)
00056             break;
00057         if (b == '\n') {
00058             line[i] = '\0';
00059             return 0;
00060         }
00061         line[i] = b;
00062     }
00063     line[i] = '\0';
00064     return -1;
00065 }
00066 
00067 static int32_t read_int(const char* line, const char** endptr, int* error)
00068 {
00069     unsigned long result = 0;
00070     for (; *line>='0' && *line<='9'; line++) {
00071         if (result > (0x7FFFFFFF - 9) / 10)
00072             *error = -1;
00073         result = 10 * result + *line - '0';
00074     }
00075     *endptr = line;
00076     return result;
00077 }
00078 
00079 static int32_t read_line_and_int(ByteIOContext * pb, int* error)
00080 {
00081     char line[RPL_LINE_LENGTH];
00082     const char *endptr;
00083     *error |= read_line(pb, line, sizeof(line));
00084     return read_int(line, &endptr, error);
00085 }
00086 
00091 static AVRational read_fps(const char* line, int* error)
00092 {
00093     int64_t num, den = 1;
00094     AVRational result;
00095     num = read_int(line, &line, error);
00096     if (*line == '.')
00097         line++;
00098     for (; *line>='0' && *line<='9'; line++) {
00099         // Truncate any numerator too large to fit into an int64_t
00100         if (num > (INT64_MAX - 9) / 10 || den > INT64_MAX / 10)
00101             break;
00102         num  = 10 * num + *line - '0';
00103         den *= 10;
00104     }
00105     if (!num)
00106         *error = -1;
00107     av_reduce(&result.num, &result.den, num, den, 0x7FFFFFFF);
00108     return result;
00109 }
00110 
00111 static int rpl_read_header(AVFormatContext *s, AVFormatParameters *ap)
00112 {
00113     ByteIOContext *pb = s->pb;
00114     RPLContext *rpl = s->priv_data;
00115     AVStream *vst = NULL, *ast = NULL;
00116     int total_audio_size;
00117     int error = 0;
00118 
00119     uint32_t i;
00120 
00121     int32_t audio_format, chunk_catalog_offset, number_of_chunks;
00122     AVRational fps;
00123 
00124     char line[RPL_LINE_LENGTH];
00125 
00126     // The header for RPL/ARMovie files is 21 lines of text
00127     // containing the various header fields.  The fields are always
00128     // in the same order, and other text besides the first
00129     // number usually isn't important.
00130     // (The spec says that there exists some significance
00131     // for the text in a few cases; samples needed.)
00132     error |= read_line(pb, line, sizeof(line));      // ARMovie
00133     error |= read_line(pb, line, sizeof(line));      // movie name
00134     av_metadata_set2(&s->metadata, "title"    , line, 0);
00135     error |= read_line(pb, line, sizeof(line));      // date/copyright
00136     av_metadata_set2(&s->metadata, "copyright", line, 0);
00137     error |= read_line(pb, line, sizeof(line));      // author and other
00138     av_metadata_set2(&s->metadata, "author"   , line, 0);
00139 
00140     // video headers
00141     vst = av_new_stream(s, 0);
00142     if (!vst)
00143         return AVERROR(ENOMEM);
00144     vst->codec->codec_type      = AVMEDIA_TYPE_VIDEO;
00145     vst->codec->codec_tag       = read_line_and_int(pb, &error);  // video format
00146     vst->codec->width           = read_line_and_int(pb, &error);  // video width
00147     vst->codec->height          = read_line_and_int(pb, &error);  // video height
00148     vst->codec->bits_per_coded_sample = read_line_and_int(pb, &error);  // video bits per sample
00149     error |= read_line(pb, line, sizeof(line));                   // video frames per second
00150     fps = read_fps(line, &error);
00151     av_set_pts_info(vst, 32, fps.den, fps.num);
00152 
00153     // Figure out the video codec
00154     switch (vst->codec->codec_tag) {
00155 #if 0
00156         case 122:
00157             vst->codec->codec_id = CODEC_ID_ESCAPE122;
00158             break;
00159 #endif
00160         case 124:
00161             vst->codec->codec_id = CODEC_ID_ESCAPE124;
00162             // The header is wrong here, at least sometimes
00163             vst->codec->bits_per_coded_sample = 16;
00164             break;
00165 #if 0
00166         case 130:
00167             vst->codec->codec_id = CODEC_ID_ESCAPE130;
00168             break;
00169 #endif
00170         default:
00171             av_log(s, AV_LOG_WARNING,
00172                    "RPL video format %i not supported yet!\n",
00173                    vst->codec->codec_tag);
00174             vst->codec->codec_id = CODEC_ID_NONE;
00175     }
00176 
00177     // Audio headers
00178 
00179     // ARMovie supports multiple audio tracks; I don't have any
00180     // samples, though. This code will ignore additional tracks.
00181     audio_format = read_line_and_int(pb, &error);  // audio format ID
00182     if (audio_format) {
00183         ast = av_new_stream(s, 0);
00184         if (!ast)
00185             return AVERROR(ENOMEM);
00186         ast->codec->codec_type      = AVMEDIA_TYPE_AUDIO;
00187         ast->codec->codec_tag       = audio_format;
00188         ast->codec->sample_rate     = read_line_and_int(pb, &error);  // audio bitrate
00189         ast->codec->channels        = read_line_and_int(pb, &error);  // number of audio channels
00190         ast->codec->bits_per_coded_sample = read_line_and_int(pb, &error);  // audio bits per sample
00191         // At least one sample uses 0 for ADPCM, which is really 4 bits
00192         // per sample.
00193         if (ast->codec->bits_per_coded_sample == 0)
00194             ast->codec->bits_per_coded_sample = 4;
00195 
00196         ast->codec->bit_rate = ast->codec->sample_rate *
00197                                ast->codec->bits_per_coded_sample *
00198                                ast->codec->channels;
00199 
00200         ast->codec->codec_id = CODEC_ID_NONE;
00201         switch (audio_format) {
00202             case 1:
00203                 if (ast->codec->bits_per_coded_sample == 16) {
00204                     // 16-bit audio is always signed
00205                     ast->codec->codec_id = CODEC_ID_PCM_S16LE;
00206                     break;
00207                 }
00208                 // There are some other formats listed as legal per the spec;
00209                 // samples needed.
00210                 break;
00211             case 101:
00212                 if (ast->codec->bits_per_coded_sample == 8) {
00213                     // The samples with this kind of audio that I have
00214                     // are all unsigned.
00215                     ast->codec->codec_id = CODEC_ID_PCM_U8;
00216                     break;
00217                 } else if (ast->codec->bits_per_coded_sample == 4) {
00218                     ast->codec->codec_id = CODEC_ID_ADPCM_IMA_EA_SEAD;
00219                     break;
00220                 }
00221                 break;
00222         }
00223         if (ast->codec->codec_id == CODEC_ID_NONE) {
00224             av_log(s, AV_LOG_WARNING,
00225                    "RPL audio format %i not supported yet!\n",
00226                    audio_format);
00227         }
00228         av_set_pts_info(ast, 32, 1, ast->codec->bit_rate);
00229     } else {
00230         for (i = 0; i < 3; i++)
00231             error |= read_line(pb, line, sizeof(line));
00232     }
00233 
00234     rpl->frames_per_chunk = read_line_and_int(pb, &error);  // video frames per chunk
00235     if (rpl->frames_per_chunk > 1 && vst->codec->codec_tag != 124)
00236         av_log(s, AV_LOG_WARNING,
00237                "Don't know how to split frames for video format %i. "
00238                "Video stream will be broken!\n", vst->codec->codec_tag);
00239 
00240     number_of_chunks = read_line_and_int(pb, &error);  // number of chunks in the file
00241     // The number in the header is actually the index of the last chunk.
00242     number_of_chunks++;
00243 
00244     error |= read_line(pb, line, sizeof(line));  // "even" chunk size in bytes
00245     error |= read_line(pb, line, sizeof(line));  // "odd" chunk size in bytes
00246     chunk_catalog_offset =                       // offset of the "chunk catalog"
00247         read_line_and_int(pb, &error);           //   (file index)
00248     error |= read_line(pb, line, sizeof(line));  // offset to "helpful" sprite
00249     error |= read_line(pb, line, sizeof(line));  // size of "helpful" sprite
00250     error |= read_line(pb, line, sizeof(line));  // offset to key frame list
00251 
00252     // Read the index
00253     url_fseek(pb, chunk_catalog_offset, SEEK_SET);
00254     total_audio_size = 0;
00255     for (i = 0; i < number_of_chunks; i++) {
00256         int64_t offset, video_size, audio_size;
00257         error |= read_line(pb, line, sizeof(line));
00258         if (3 != sscanf(line, "%"PRId64" , %"PRId64" ; %"PRId64,
00259                         &offset, &video_size, &audio_size))
00260             error = -1;
00261         av_add_index_entry(vst, offset, i * rpl->frames_per_chunk,
00262                            video_size, rpl->frames_per_chunk, 0);
00263         if (ast)
00264             av_add_index_entry(ast, offset + video_size, total_audio_size,
00265                                audio_size, audio_size * 8, 0);
00266         total_audio_size += audio_size * 8;
00267     }
00268 
00269     if (error) return AVERROR(EIO);
00270 
00271     return 0;
00272 }
00273 
00274 static int rpl_read_packet(AVFormatContext *s, AVPacket *pkt)
00275 {
00276     RPLContext *rpl = s->priv_data;
00277     ByteIOContext *pb = s->pb;
00278     AVStream* stream;
00279     AVIndexEntry* index_entry;
00280     uint32_t ret;
00281 
00282     if (rpl->chunk_part == s->nb_streams) {
00283         rpl->chunk_number++;
00284         rpl->chunk_part = 0;
00285     }
00286 
00287     stream = s->streams[rpl->chunk_part];
00288 
00289     if (rpl->chunk_number >= stream->nb_index_entries)
00290         return -1;
00291 
00292     index_entry = &stream->index_entries[rpl->chunk_number];
00293 
00294     if (rpl->frame_in_part == 0)
00295         if (url_fseek(pb, index_entry->pos, SEEK_SET) < 0)
00296             return AVERROR(EIO);
00297 
00298     if (stream->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
00299         stream->codec->codec_tag == 124) {
00300         // We have to split Escape 124 frames because there are
00301         // multiple frames per chunk in Escape 124 samples.
00302         uint32_t frame_size, frame_flags;
00303 
00304         frame_flags = get_le32(pb);
00305         frame_size = get_le32(pb);
00306         if (url_fseek(pb, -8, SEEK_CUR) < 0)
00307             return AVERROR(EIO);
00308 
00309         ret = av_get_packet(pb, pkt, frame_size);
00310         if (ret != frame_size) {
00311             av_free_packet(pkt);
00312             return AVERROR(EIO);
00313         }
00314         pkt->duration = 1;
00315         pkt->pts = index_entry->timestamp + rpl->frame_in_part;
00316         pkt->stream_index = rpl->chunk_part;
00317 
00318         rpl->frame_in_part++;
00319         if (rpl->frame_in_part == rpl->frames_per_chunk) {
00320             rpl->frame_in_part = 0;
00321             rpl->chunk_part++;
00322         }
00323     } else {
00324         ret = av_get_packet(pb, pkt, index_entry->size);
00325         if (ret != index_entry->size) {
00326             av_free_packet(pkt);
00327             return AVERROR(EIO);
00328         }
00329 
00330         if (stream->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
00331             // frames_per_chunk should always be one here; the header
00332             // parsing will warn if it isn't.
00333             pkt->duration = rpl->frames_per_chunk;
00334         } else {
00335             // All the audio codecs supported in this container
00336             // (at least so far) are constant-bitrate.
00337             pkt->duration = ret * 8;
00338         }
00339         pkt->pts = index_entry->timestamp;
00340         pkt->stream_index = rpl->chunk_part;
00341         rpl->chunk_part++;
00342     }
00343 
00344     // None of the Escape formats have keyframes, and the ADPCM
00345     // format used doesn't have keyframes.
00346     if (rpl->chunk_number == 0 && rpl->frame_in_part == 0)
00347         pkt->flags |= AV_PKT_FLAG_KEY;
00348 
00349     return ret;
00350 }
00351 
00352 AVInputFormat rpl_demuxer = {
00353     "rpl",
00354     NULL_IF_CONFIG_SMALL("RPL/ARMovie format"),
00355     sizeof(RPLContext),
00356     rpl_probe,
00357     rpl_read_header,
00358     rpl_read_packet,
00359 };

Generated on Fri Sep 16 2011 17:17:50 for FFmpeg by  doxygen 1.7.1