From cb96da490265a0a798324ccce1c87dca9acbf6e9 Mon Sep 17 00:00:00 2001 From: Sascha Sommer Date: Fri, 21 Mar 2008 14:02:13 +0000 Subject: rl2 demuxer Originally committed as revision 12545 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavformat/rl2.c | 299 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 299 insertions(+) create mode 100644 libavformat/rl2.c (limited to 'libavformat/rl2.c') diff --git a/libavformat/rl2.c b/libavformat/rl2.c new file mode 100644 index 0000000000..30f065bb81 --- /dev/null +++ b/libavformat/rl2.c @@ -0,0 +1,299 @@ +/* + * 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 rl2.c + * @author Sascha Sommer (saschasommer@freenet.de) + * For more information regarding the RL2 file format, visit: + * 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 "avformat.h" + +#define EXTRADATA1_SIZE (6 + 256 * 3) ///< video base, clr, palette + +#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]; ///< indices 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 + * @param ap format parameters + * @return 0 on success, AVERROR otherwise + */ +static av_cold int rl2_read_header(AVFormatContext *s, + AVFormatParameters *ap) +{ + ByteIOContext *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; + int data_size; + unsigned short encoding_method; + 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; + + url_fskip(pb,4); /* skip FORM tag */ + back_size = get_le32(pb); /** get size of the background frame */ + signature = get_be32(pb); + data_size = get_be32(pb); + frame_count = get_le32(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; + + encoding_method = get_le16(pb); + sound_rate = get_le16(pb); + rate = get_le16(pb); + channels = get_le16(pb); + def_sound_size = get_le16(pb); + + /** setup video stream */ + st = av_new_stream(s, 0); + if(!st) + return AVERROR(ENOMEM); + + st->codec->codec_type = CODEC_TYPE_VIDEO; + st->codec->codec_id = 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; + + if(signature == RLV3_TAG && back_size > 0) + st->codec->extradata_size += back_size; + + st->codec->extradata = av_mallocz(st->codec->extradata_size + + FF_INPUT_BUFFER_PADDING_SIZE); + if(!st->codec->extradata) + return AVERROR(ENOMEM); + + if(get_buffer(pb,st->codec->extradata,st->codec->extradata_size) != + st->codec->extradata_size) + return AVERROR(EIO); + + /** setup audio stream if present */ + if(sound_rate){ + pts_num = def_sound_size; + pts_den = rate; + + st = av_new_stream(s, 0); + if (!st) + return AVERROR(ENOMEM); + st->codec->codec_type = CODEC_TYPE_AUDIO; + st->codec->codec_id = CODEC_ID_PCM_U8; + st->codec->codec_tag = 1; + st->codec->channels = channels; + st->codec->bits_per_sample = 8; + st->codec->sample_rate = rate; + st->codec->bit_rate = st->codec->channels * st->codec->sample_rate * + st->codec->bits_per_sample; + st->codec->block_align = st->codec->channels * + st->codec->bits_per_sample / 8; + av_set_pts_info(st,32,1,rate); + } + + av_set_pts_info(s->streams[0], 32, pts_num, pts_den); + + 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)); + + 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] = get_le32(pb); + for(i=0; i < frame_count;i++) + chunk_offset[i] = get_le32(pb); + for(i=0; i < frame_count;i++) + audio_size[i] = get_le32(pb) & 0xFFFF; + + /** build the sample index */ + for(i=0;i chunk_size[i]){ + ret = AVERROR_INVALIDDATA; + break; + } + + 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); + + return ret; +} + +/** + * 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; + ByteIOContext *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; inb_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; + } + } + + if(stream_id == -1) + return AVERROR(EIO); + + ++rl2->index_pos[stream_id]; + + /** position the stream (will probably be there anyway) */ + url_fseek(pb, sample->pos, SEEK_SET); + + /** fill the packet */ + ret = av_get_packet(pb, pkt, sample->size); + if(ret != sample->size){ + av_free_packet(pkt); + return AVERROR(EIO); + } + + pkt->stream_index = stream_id; + pkt->pts = sample->timestamp; + + return ret; +} + +/** + * 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; + + rl2->index_pos[stream_index] = index; + timestamp = st->index_entries[index].timestamp; + + 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); + + if(index < 0) + index = 0; + + rl2->index_pos[i] = index; + } + + return 0; +} + +AVInputFormat rl2_demuxer = { + "rl2", + "rl2 format", + sizeof(Rl2DemuxContext), + rl2_probe, + rl2_read_header, + rl2_read_packet, + NULL, + rl2_read_seek, +}; + -- cgit v1.2.3