1/*
2 * Tiertex Limited SEQ File Demuxer
3 * Copyright (c) 2006 Gregory Montoir (cyx@users.sourceforge.net)
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/**
23 * @file libavformat/tiertexseq.c
24 * Tiertex Limited SEQ file demuxer
25 */
26
27#include "avformat.h"
28
29#define SEQ_FRAME_SIZE         6144
30#define SEQ_FRAME_W            256
31#define SEQ_FRAME_H            128
32#define SEQ_NUM_FRAME_BUFFERS  30
33#define SEQ_AUDIO_BUFFER_SIZE  882
34#define SEQ_SAMPLE_RATE        22050
35#define SEQ_FRAME_RATE         25
36
37
38typedef struct TiertexSeqFrameBuffer {
39    int fill_size;
40    int data_size;
41    unsigned char *data;
42} TiertexSeqFrameBuffer;
43
44typedef struct SeqDemuxContext {
45    int audio_stream_index;
46    int video_stream_index;
47    int current_frame_pts;
48    int current_frame_offs;
49    TiertexSeqFrameBuffer frame_buffers[SEQ_NUM_FRAME_BUFFERS];
50    int frame_buffers_count;
51    unsigned int current_audio_data_size;
52    unsigned int current_audio_data_offs;
53    unsigned int current_pal_data_size;
54    unsigned int current_pal_data_offs;
55    unsigned int current_video_data_size;
56    unsigned char *current_video_data_ptr;
57    int audio_buffer_full;
58} SeqDemuxContext;
59
60
61static int seq_probe(AVProbeData *p)
62{
63    int i;
64
65    if (p->buf_size < 258)
66        return 0;
67
68    /* there's no real header in a .seq file, the only thing they have in common */
69    /* is the first 256 bytes of the file which are always filled with 0 */
70    for (i = 0; i < 256; i++)
71        if (p->buf[i])
72            return 0;
73
74    if(p->buf[256]==0 && p->buf[257]==0)
75        return 0;
76
77    /* only one fourth of the score since the previous check is too naive */
78    return AVPROBE_SCORE_MAX / 4;
79}
80
81static int seq_init_frame_buffers(SeqDemuxContext *seq, ByteIOContext *pb)
82{
83    int i, sz;
84    TiertexSeqFrameBuffer *seq_buffer;
85
86    url_fseek(pb, 256, SEEK_SET);
87
88    for (i = 0; i < SEQ_NUM_FRAME_BUFFERS; i++) {
89        sz = get_le16(pb);
90        if (sz == 0)
91            break;
92        else {
93            seq_buffer = &seq->frame_buffers[i];
94            seq_buffer->fill_size = 0;
95            seq_buffer->data_size = sz;
96            seq_buffer->data = av_malloc(sz);
97            if (!seq_buffer->data)
98                return AVERROR(ENOMEM);
99        }
100    }
101    seq->frame_buffers_count = i;
102    return 0;
103}
104
105static int seq_fill_buffer(SeqDemuxContext *seq, ByteIOContext *pb, int buffer_num, unsigned int data_offs, int data_size)
106{
107    TiertexSeqFrameBuffer *seq_buffer;
108
109    if (buffer_num >= SEQ_NUM_FRAME_BUFFERS)
110        return AVERROR_INVALIDDATA;
111
112    seq_buffer = &seq->frame_buffers[buffer_num];
113    if (seq_buffer->fill_size + data_size > seq_buffer->data_size || data_size <= 0)
114        return AVERROR_INVALIDDATA;
115
116    url_fseek(pb, seq->current_frame_offs + data_offs, SEEK_SET);
117    if (get_buffer(pb, seq_buffer->data + seq_buffer->fill_size, data_size) != data_size)
118        return AVERROR(EIO);
119
120    seq_buffer->fill_size += data_size;
121    return 0;
122}
123
124static int seq_parse_frame_data(SeqDemuxContext *seq, ByteIOContext *pb)
125{
126    unsigned int offset_table[4], buffer_num[4];
127    TiertexSeqFrameBuffer *seq_buffer;
128    int i, e, err;
129
130    seq->current_frame_offs += SEQ_FRAME_SIZE;
131    url_fseek(pb, seq->current_frame_offs, SEEK_SET);
132
133    /* sound data */
134    seq->current_audio_data_offs = get_le16(pb);
135    if (seq->current_audio_data_offs) {
136        seq->current_audio_data_size = SEQ_AUDIO_BUFFER_SIZE * 2;
137    } else {
138        seq->current_audio_data_size = 0;
139    }
140
141    /* palette data */
142    seq->current_pal_data_offs = get_le16(pb);
143    if (seq->current_pal_data_offs) {
144        seq->current_pal_data_size = 768;
145    } else {
146        seq->current_pal_data_size = 0;
147    }
148
149    /* video data */
150    for (i = 0; i < 4; i++)
151        buffer_num[i] = get_byte(pb);
152
153    for (i = 0; i < 4; i++)
154        offset_table[i] = get_le16(pb);
155
156    for (i = 0; i < 3; i++) {
157        if (offset_table[i]) {
158            for (e = i + 1; e < 3 && offset_table[e] == 0; e++);
159            err = seq_fill_buffer(seq, pb, buffer_num[1 + i],
160              offset_table[i],
161              offset_table[e] - offset_table[i]);
162            if (err)
163                return err;
164        }
165    }
166
167    if (buffer_num[0] != 255) {
168        if (buffer_num[0] >= SEQ_NUM_FRAME_BUFFERS)
169            return AVERROR_INVALIDDATA;
170
171        seq_buffer = &seq->frame_buffers[buffer_num[0]];
172        seq->current_video_data_size = seq_buffer->fill_size;
173        seq->current_video_data_ptr  = seq_buffer->data;
174        seq_buffer->fill_size = 0;
175    } else {
176        seq->current_video_data_size = 0;
177        seq->current_video_data_ptr  = 0;
178    }
179
180    return 0;
181}
182
183static int seq_read_header(AVFormatContext *s, AVFormatParameters *ap)
184{
185    int i, rc;
186    SeqDemuxContext *seq = s->priv_data;
187    ByteIOContext *pb = s->pb;
188    AVStream *st;
189
190    /* init internal buffers */
191    rc = seq_init_frame_buffers(seq, pb);
192    if (rc)
193        return rc;
194
195    seq->current_frame_offs = 0;
196
197    /* preload (no audio data, just buffer operations related data) */
198    for (i = 1; i <= 100; i++) {
199        rc = seq_parse_frame_data(seq, pb);
200        if (rc)
201            return rc;
202    }
203
204    seq->current_frame_pts = 0;
205
206    seq->audio_buffer_full = 0;
207
208    /* initialize the video decoder stream */
209    st = av_new_stream(s, 0);
210    if (!st)
211        return AVERROR(ENOMEM);
212
213    av_set_pts_info(st, 32, 1, SEQ_FRAME_RATE);
214    seq->video_stream_index = st->index;
215    st->codec->codec_type = CODEC_TYPE_VIDEO;
216    st->codec->codec_id = CODEC_ID_TIERTEXSEQVIDEO;
217    st->codec->codec_tag = 0;  /* no fourcc */
218    st->codec->width = SEQ_FRAME_W;
219    st->codec->height = SEQ_FRAME_H;
220
221    /* initialize the audio decoder stream */
222    st = av_new_stream(s, 0);
223    if (!st)
224        return AVERROR(ENOMEM);
225
226    av_set_pts_info(st, 32, 1, SEQ_SAMPLE_RATE);
227    seq->audio_stream_index = st->index;
228    st->codec->codec_type = CODEC_TYPE_AUDIO;
229    st->codec->codec_id = CODEC_ID_PCM_S16BE;
230    st->codec->codec_tag = 0;  /* no tag */
231    st->codec->channels = 1;
232    st->codec->sample_rate = SEQ_SAMPLE_RATE;
233    st->codec->bits_per_coded_sample = 16;
234    st->codec->bit_rate = st->codec->sample_rate * st->codec->bits_per_coded_sample * st->codec->channels;
235    st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample;
236
237    return 0;
238}
239
240static int seq_read_packet(AVFormatContext *s, AVPacket *pkt)
241{
242    int rc;
243    SeqDemuxContext *seq = s->priv_data;
244    ByteIOContext *pb = s->pb;
245
246    if (!seq->audio_buffer_full) {
247        rc = seq_parse_frame_data(seq, pb);
248        if (rc)
249            return rc;
250
251        /* video packet */
252        if (seq->current_pal_data_size + seq->current_video_data_size != 0) {
253            if (av_new_packet(pkt, 1 + seq->current_pal_data_size + seq->current_video_data_size))
254                return AVERROR(ENOMEM);
255
256            pkt->data[0] = 0;
257            if (seq->current_pal_data_size) {
258                pkt->data[0] |= 1;
259                url_fseek(pb, seq->current_frame_offs + seq->current_pal_data_offs, SEEK_SET);
260                if (get_buffer(pb, &pkt->data[1], seq->current_pal_data_size) != seq->current_pal_data_size)
261                    return AVERROR(EIO);
262            }
263            if (seq->current_video_data_size) {
264                pkt->data[0] |= 2;
265                memcpy(&pkt->data[1 + seq->current_pal_data_size],
266                  seq->current_video_data_ptr,
267                  seq->current_video_data_size);
268            }
269            pkt->stream_index = seq->video_stream_index;
270            pkt->pts = seq->current_frame_pts;
271
272            /* sound buffer will be processed on next read_packet() call */
273            seq->audio_buffer_full = 1;
274            return 0;
275       }
276    }
277
278    /* audio packet */
279    if (seq->current_audio_data_offs == 0) /* end of data reached */
280        return AVERROR(EIO);
281
282    url_fseek(pb, seq->current_frame_offs + seq->current_audio_data_offs, SEEK_SET);
283    rc = av_get_packet(pb, pkt, seq->current_audio_data_size);
284    if (rc < 0)
285        return rc;
286
287    pkt->stream_index = seq->audio_stream_index;
288    seq->current_frame_pts++;
289
290    seq->audio_buffer_full = 0;
291    return 0;
292}
293
294static int seq_read_close(AVFormatContext *s)
295{
296    int i;
297    SeqDemuxContext *seq = s->priv_data;
298
299    for (i = 0; i < SEQ_NUM_FRAME_BUFFERS; i++)
300        av_free(seq->frame_buffers[i].data);
301
302    return 0;
303}
304
305AVInputFormat tiertexseq_demuxer = {
306    "tiertexseq",
307    NULL_IF_CONFIG_SMALL("Tiertex Limited SEQ format"),
308    sizeof(SeqDemuxContext),
309    seq_probe,
310    seq_read_header,
311    seq_read_packet,
312    seq_read_close,
313};
314