1/*
2 * DXA demuxer
3 * Copyright (c) 2007 Konstantin Shishkov
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#include "libavutil/intreadwrite.h"
23#include "avformat.h"
24#include "riff.h"
25
26#define DXA_EXTRA_SIZE  9
27
28typedef struct{
29    int frames;
30    int has_sound;
31    int bpc;
32    uint32_t bytes_left;
33    int64_t wavpos, vidpos;
34    int readvid;
35}DXAContext;
36
37static int dxa_probe(AVProbeData *p)
38{
39    /* check file header */
40    if (p->buf[0] == 'D' && p->buf[1] == 'E' &&
41        p->buf[2] == 'X' && p->buf[3] == 'A')
42        return AVPROBE_SCORE_MAX;
43    else
44        return 0;
45}
46
47static int dxa_read_header(AVFormatContext *s, AVFormatParameters *ap)
48{
49    ByteIOContext *pb = s->pb;
50    DXAContext *c = s->priv_data;
51    AVStream *st, *ast;
52    uint32_t tag;
53    int32_t fps;
54    int w, h;
55    int num, den;
56    int flags;
57
58    tag = get_le32(pb);
59    if (tag != MKTAG('D', 'E', 'X', 'A'))
60        return -1;
61    flags = get_byte(pb);
62    c->frames = get_be16(pb);
63    if(!c->frames){
64        av_log(s, AV_LOG_ERROR, "File contains no frames ???\n");
65        return -1;
66    }
67
68    fps = get_be32(pb);
69    if(fps > 0){
70        den = 1000;
71        num = fps;
72    }else if (fps < 0){
73        den = 100000;
74        num = -fps;
75    }else{
76        den = 10;
77        num = 1;
78    }
79    w = get_be16(pb);
80    h = get_be16(pb);
81    c->has_sound = 0;
82
83    st = av_new_stream(s, 0);
84    if (!st)
85        return -1;
86
87    // Parse WAV data header
88    if(get_le32(pb) == MKTAG('W', 'A', 'V', 'E')){
89        uint32_t size, fsize;
90        c->has_sound = 1;
91        size = get_be32(pb);
92        c->vidpos = url_ftell(pb) + size;
93        url_fskip(pb, 16);
94        fsize = get_le32(pb);
95
96        ast = av_new_stream(s, 0);
97        if (!ast)
98            return -1;
99        get_wav_header(pb, ast->codec, fsize);
100        // find 'data' chunk
101        while(url_ftell(pb) < c->vidpos && !url_feof(pb)){
102            tag = get_le32(pb);
103            fsize = get_le32(pb);
104            if(tag == MKTAG('d', 'a', 't', 'a')) break;
105            url_fskip(pb, fsize);
106        }
107        c->bpc = (fsize + c->frames - 1) / c->frames;
108        if(ast->codec->block_align)
109            c->bpc = ((c->bpc + ast->codec->block_align - 1) / ast->codec->block_align) * ast->codec->block_align;
110        c->bytes_left = fsize;
111        c->wavpos = url_ftell(pb);
112        url_fseek(pb, c->vidpos, SEEK_SET);
113    }
114
115    /* now we are ready: build format streams */
116    st->codec->codec_type = CODEC_TYPE_VIDEO;
117    st->codec->codec_id   = CODEC_ID_DXA;
118    st->codec->width      = w;
119    st->codec->height     = h;
120    av_reduce(&den, &num, den, num, (1UL<<31)-1);
121    av_set_pts_info(st, 33, num, den);
122    /* flags & 0x80 means that image is interlaced,
123     * flags & 0x40 means that image has double height
124     * either way set true height
125     */
126    if(flags & 0xC0){
127        st->codec->height >>= 1;
128    }
129    c->readvid = !c->has_sound;
130    c->vidpos  = url_ftell(pb);
131    s->start_time = 0;
132    s->duration = (int64_t)c->frames * AV_TIME_BASE * num / den;
133    av_log(s, AV_LOG_DEBUG, "%d frame(s)\n",c->frames);
134
135    return 0;
136}
137
138static int dxa_read_packet(AVFormatContext *s, AVPacket *pkt)
139{
140    DXAContext *c = s->priv_data;
141    int ret;
142    uint32_t size;
143    uint8_t buf[DXA_EXTRA_SIZE], pal[768+4];
144    int pal_size = 0;
145
146    if(!c->readvid && c->has_sound && c->bytes_left){
147        c->readvid = 1;
148        url_fseek(s->pb, c->wavpos, SEEK_SET);
149        size = FFMIN(c->bytes_left, c->bpc);
150        ret = av_get_packet(s->pb, pkt, size);
151        pkt->stream_index = 1;
152        if(ret != size)
153            return AVERROR(EIO);
154        c->bytes_left -= size;
155        c->wavpos = url_ftell(s->pb);
156        return 0;
157    }
158    url_fseek(s->pb, c->vidpos, SEEK_SET);
159    while(!url_feof(s->pb) && c->frames){
160        get_buffer(s->pb, buf, 4);
161        switch(AV_RL32(buf)){
162        case MKTAG('N', 'U', 'L', 'L'):
163            if(av_new_packet(pkt, 4 + pal_size) < 0)
164                return AVERROR(ENOMEM);
165            pkt->stream_index = 0;
166            if(pal_size) memcpy(pkt->data, pal, pal_size);
167            memcpy(pkt->data + pal_size, buf, 4);
168            c->frames--;
169            c->vidpos = url_ftell(s->pb);
170            c->readvid = 0;
171            return 0;
172        case MKTAG('C', 'M', 'A', 'P'):
173            pal_size = 768+4;
174            memcpy(pal, buf, 4);
175            get_buffer(s->pb, pal + 4, 768);
176            break;
177        case MKTAG('F', 'R', 'A', 'M'):
178            get_buffer(s->pb, buf + 4, DXA_EXTRA_SIZE - 4);
179            size = AV_RB32(buf + 5);
180            if(size > 0xFFFFFF){
181                av_log(s, AV_LOG_ERROR, "Frame size is too big: %d\n", size);
182                return -1;
183            }
184            if(av_new_packet(pkt, size + DXA_EXTRA_SIZE + pal_size) < 0)
185                return AVERROR(ENOMEM);
186            memcpy(pkt->data + pal_size, buf, DXA_EXTRA_SIZE);
187            ret = get_buffer(s->pb, pkt->data + DXA_EXTRA_SIZE + pal_size, size);
188            if(ret != size){
189                av_free_packet(pkt);
190                return AVERROR(EIO);
191            }
192            if(pal_size) memcpy(pkt->data, pal, pal_size);
193            pkt->stream_index = 0;
194            c->frames--;
195            c->vidpos = url_ftell(s->pb);
196            c->readvid = 0;
197            return 0;
198        default:
199            av_log(s, AV_LOG_ERROR, "Unknown tag %c%c%c%c\n", buf[0], buf[1], buf[2], buf[3]);
200            return -1;
201        }
202    }
203    return AVERROR(EIO);
204}
205
206AVInputFormat dxa_demuxer = {
207    "dxa",
208    NULL_IF_CONFIG_SMALL("DXA"),
209    sizeof(DXAContext),
210    dxa_probe,
211    dxa_read_header,
212    dxa_read_packet,
213};
214