0,0 → 1,298 |
/* |
* RL2 Format Demuxer |
* Copyright (c) 2008 Sascha Sommer (saschasommer@freenet.de) |
* |
* This file is part of FFmpeg. |
* |
* FFmpeg is free software; you can redistribute it and/or |
* modify it under the terms of the GNU Lesser General Public |
* License as published by the Free Software Foundation; either |
* version 2.1 of the License, or (at your option) any later version. |
* |
* FFmpeg is distributed in the hope that it will be useful, |
* but WITHOUT ANY WARRANTY; without even the implied warranty of |
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
* Lesser General Public License for more details. |
* |
* You should have received a copy of the GNU Lesser General Public |
* License along with FFmpeg; if not, write to the Free Software |
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
*/ |
|
/** |
* RL2 file demuxer |
* @file |
* @author Sascha Sommer (saschasommer@freenet.de) |
* @see http://wiki.multimedia.cx/index.php?title=RL2 |
* |
* extradata: |
* 2 byte le initial drawing offset within 320x200 viewport |
* 4 byte le number of used colors |
* 256 * 3 bytes rgb palette |
* optional background_frame |
*/ |
|
#include "libavutil/intreadwrite.h" |
#include "libavutil/mathematics.h" |
#include "avformat.h" |
#include "internal.h" |
|
#define EXTRADATA1_SIZE (6 + 256 * 3) ///< video base, clr, palette |
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#define FORM_TAG MKBETAG('F', 'O', 'R', 'M') |
#define RLV2_TAG MKBETAG('R', 'L', 'V', '2') |
#define RLV3_TAG MKBETAG('R', 'L', 'V', '3') |
|
typedef struct Rl2DemuxContext { |
unsigned int index_pos[2]; ///< indexes in the sample tables |
} Rl2DemuxContext; |
|
|
/** |
* check if the file is in rl2 format |
* @param p probe buffer |
* @return 0 when the probe buffer does not contain rl2 data, > 0 otherwise |
*/ |
static int rl2_probe(AVProbeData *p) |
{ |
|
if(AV_RB32(&p->buf[0]) != FORM_TAG) |
return 0; |
|
if(AV_RB32(&p->buf[8]) != RLV2_TAG && |
AV_RB32(&p->buf[8]) != RLV3_TAG) |
return 0; |
|
return AVPROBE_SCORE_MAX; |
} |
|
/** |
* read rl2 header data and setup the avstreams |
* @param s demuxer context |
* @return 0 on success, AVERROR otherwise |
*/ |
static av_cold int rl2_read_header(AVFormatContext *s) |
{ |
AVIOContext *pb = s->pb; |
AVStream *st; |
unsigned int frame_count; |
unsigned int audio_frame_counter = 0; |
unsigned int video_frame_counter = 0; |
unsigned int back_size; |
unsigned short sound_rate; |
unsigned short rate; |
unsigned short channels; |
unsigned short def_sound_size; |
unsigned int signature; |
unsigned int pts_den = 11025; /* video only case */ |
unsigned int pts_num = 1103; |
unsigned int* chunk_offset = NULL; |
int* chunk_size = NULL; |
int* audio_size = NULL; |
int i; |
int ret = 0; |
|
avio_skip(pb,4); /* skip FORM tag */ |
back_size = avio_rl32(pb); /**< get size of the background frame */ |
signature = avio_rb32(pb); |
avio_skip(pb, 4); /* data size */ |
frame_count = avio_rl32(pb); |
|
/* disallow back_sizes and frame_counts that may lead to overflows later */ |
if(back_size > INT_MAX/2 || frame_count > INT_MAX / sizeof(uint32_t)) |
return AVERROR_INVALIDDATA; |
|
avio_skip(pb, 2); /* encoding mentod */ |
sound_rate = avio_rl16(pb); |
rate = avio_rl16(pb); |
channels = avio_rl16(pb); |
def_sound_size = avio_rl16(pb); |
|
/** setup video stream */ |
st = avformat_new_stream(s, NULL); |
if(!st) |
return AVERROR(ENOMEM); |
|
st->codec->codec_type = AVMEDIA_TYPE_VIDEO; |
st->codec->codec_id = AV_CODEC_ID_RL2; |
st->codec->codec_tag = 0; /* no fourcc */ |
st->codec->width = 320; |
st->codec->height = 200; |
|
/** allocate and fill extradata */ |
st->codec->extradata_size = EXTRADATA1_SIZE; |
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if(signature == RLV3_TAG && back_size > 0) |
st->codec->extradata_size += back_size; |
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if(ff_alloc_extradata(st->codec, st->codec->extradata_size)) |
return AVERROR(ENOMEM); |
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if(avio_read(pb,st->codec->extradata,st->codec->extradata_size) != |
st->codec->extradata_size) |
return AVERROR(EIO); |
|
/** setup audio stream if present */ |
if(sound_rate){ |
if (!channels || channels > 42) { |
av_log(s, AV_LOG_ERROR, "Invalid number of channels: %d\n", channels); |
return AVERROR_INVALIDDATA; |
} |
|
pts_num = def_sound_size; |
pts_den = rate; |
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st = avformat_new_stream(s, NULL); |
if (!st) |
return AVERROR(ENOMEM); |
st->codec->codec_type = AVMEDIA_TYPE_AUDIO; |
st->codec->codec_id = AV_CODEC_ID_PCM_U8; |
st->codec->codec_tag = 1; |
st->codec->channels = channels; |
st->codec->bits_per_coded_sample = 8; |
st->codec->sample_rate = rate; |
st->codec->bit_rate = st->codec->channels * st->codec->sample_rate * |
st->codec->bits_per_coded_sample; |
st->codec->block_align = st->codec->channels * |
st->codec->bits_per_coded_sample / 8; |
avpriv_set_pts_info(st,32,1,rate); |
} |
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avpriv_set_pts_info(s->streams[0], 32, pts_num, pts_den); |
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chunk_size = av_malloc(frame_count * sizeof(uint32_t)); |
audio_size = av_malloc(frame_count * sizeof(uint32_t)); |
chunk_offset = av_malloc(frame_count * sizeof(uint32_t)); |
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if(!chunk_size || !audio_size || !chunk_offset){ |
av_free(chunk_size); |
av_free(audio_size); |
av_free(chunk_offset); |
return AVERROR(ENOMEM); |
} |
|
/** read offset and size tables */ |
for(i=0; i < frame_count;i++) |
chunk_size[i] = avio_rl32(pb); |
for(i=0; i < frame_count;i++) |
chunk_offset[i] = avio_rl32(pb); |
for(i=0; i < frame_count;i++) |
audio_size[i] = avio_rl32(pb) & 0xFFFF; |
|
/** build the sample index */ |
for(i=0;i<frame_count;i++){ |
if(chunk_size[i] < 0 || audio_size[i] > chunk_size[i]){ |
ret = AVERROR_INVALIDDATA; |
break; |
} |
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if(sound_rate && audio_size[i]){ |
av_add_index_entry(s->streams[1], chunk_offset[i], |
audio_frame_counter,audio_size[i], 0, AVINDEX_KEYFRAME); |
audio_frame_counter += audio_size[i] / channels; |
} |
av_add_index_entry(s->streams[0], chunk_offset[i] + audio_size[i], |
video_frame_counter,chunk_size[i]-audio_size[i],0,AVINDEX_KEYFRAME); |
++video_frame_counter; |
} |
|
|
av_free(chunk_size); |
av_free(audio_size); |
av_free(chunk_offset); |
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return ret; |
} |
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/** |
* read a single audio or video packet |
* @param s demuxer context |
* @param pkt the packet to be filled |
* @return 0 on success, AVERROR otherwise |
*/ |
static int rl2_read_packet(AVFormatContext *s, |
AVPacket *pkt) |
{ |
Rl2DemuxContext *rl2 = s->priv_data; |
AVIOContext *pb = s->pb; |
AVIndexEntry *sample = NULL; |
int i; |
int ret = 0; |
int stream_id = -1; |
int64_t pos = INT64_MAX; |
|
/** check if there is a valid video or audio entry that can be used */ |
for(i=0; i<s->nb_streams; i++){ |
if(rl2->index_pos[i] < s->streams[i]->nb_index_entries |
&& s->streams[i]->index_entries[ rl2->index_pos[i] ].pos < pos){ |
sample = &s->streams[i]->index_entries[ rl2->index_pos[i] ]; |
pos= sample->pos; |
stream_id= i; |
} |
} |
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if(stream_id == -1) |
return AVERROR_EOF; |
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++rl2->index_pos[stream_id]; |
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/** position the stream (will probably be there anyway) */ |
avio_seek(pb, sample->pos, SEEK_SET); |
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/** fill the packet */ |
ret = av_get_packet(pb, pkt, sample->size); |
if(ret != sample->size){ |
av_free_packet(pkt); |
return AVERROR(EIO); |
} |
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pkt->stream_index = stream_id; |
pkt->pts = sample->timestamp; |
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return ret; |
} |
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/** |
* seek to a new timestamp |
* @param s demuxer context |
* @param stream_index index of the stream that should be seeked |
* @param timestamp wanted timestamp |
* @param flags direction and seeking mode |
* @return 0 on success, -1 otherwise |
*/ |
static int rl2_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags) |
{ |
AVStream *st = s->streams[stream_index]; |
Rl2DemuxContext *rl2 = s->priv_data; |
int i; |
int index = av_index_search_timestamp(st, timestamp, flags); |
if(index < 0) |
return -1; |
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rl2->index_pos[stream_index] = index; |
timestamp = st->index_entries[index].timestamp; |
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for(i=0; i < s->nb_streams; i++){ |
AVStream *st2 = s->streams[i]; |
index = av_index_search_timestamp(st2, |
av_rescale_q(timestamp, st->time_base, st2->time_base), |
flags | AVSEEK_FLAG_BACKWARD); |
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if(index < 0) |
index = 0; |
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rl2->index_pos[i] = index; |
} |
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return 0; |
} |
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AVInputFormat ff_rl2_demuxer = { |
.name = "rl2", |
.long_name = NULL_IF_CONFIG_SMALL("RL2"), |
.priv_data_size = sizeof(Rl2DemuxContext), |
.read_probe = rl2_probe, |
.read_header = rl2_read_header, |
.read_packet = rl2_read_packet, |
.read_seek = rl2_read_seek, |
}; |