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authorSascha Sommer <saschasommer@freenet.de>2008-03-21 14:02:13 +0000
committerSascha Sommer <saschasommer@freenet.de>2008-03-21 14:02:13 +0000
commitcb96da490265a0a798324ccce1c87dca9acbf6e9 (patch)
tree3758aaec2d652f6b6baa911620ec1182120ae640 /libavformat/rl2.c
parent084d8faa2131f855e069c3f526a1b3619f039b28 (diff)
downloadffmpeg-cb96da490265a0a798324ccce1c87dca9acbf6e9.tar.gz
rl2 demuxer
Originally committed as revision 12545 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavformat/rl2.c')
-rw-r--r--libavformat/rl2.c299
1 files changed, 299 insertions, 0 deletions
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<frame_count;i++){
+ if(chunk_size[i] < 0 || audio_size[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; 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;
+ }
+ }
+
+ 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,
+};
+