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    int w, h;
40    if (p->buf_size < 15)
41        return 0;
42    w = AV_RB16(p->buf + 11);
43    h = AV_RB16(p->buf + 13);
44    /* check file header */
45    if (p->buf[0] == 'D' && p->buf[1] == 'E' &&
46        p->buf[2] == 'X' && p->buf[3] == 'A' &&
47        w && w <= 2048 && h && h <= 2048)
48        return AVPROBE_SCORE_MAX;
49    else
50        return 0;
51}
52
53static int dxa_read_header(AVFormatContext *s, AVFormatParameters *ap)
54{
55    ByteIOContext *pb = s->pb;
56    DXAContext *c = s->priv_data;
57    AVStream *st, *ast;
58    uint32_t tag;
59    int32_t fps;
60    int w, h;
61    int num, den;
62    int flags;
63
64    tag = get_le32(pb);
65    if (tag != MKTAG('D', 'E', 'X', 'A'))
66        return -1;
67    flags = get_byte(pb);
68    c->frames = get_be16(pb);
69    if(!c->frames){
70        av_log(s, AV_LOG_ERROR, "File contains no frames ???\n");
71        return -1;
72    }
73
74    fps = get_be32(pb);
75    if(fps > 0){
76        den = 1000;
77        num = fps;
78    }else if (fps < 0){
79        den = 100000;
80        num = -fps;
81    }else{
82        den = 10;
83        num = 1;
84    }
85    w = get_be16(pb);
86    h = get_be16(pb);
87    c->has_sound = 0;
88
89    st = av_new_stream(s, 0);
90    if (!st)
91        return -1;
92
93    // Parse WAV data header
94    if(get_le32(pb) == MKTAG('W', 'A', 'V', 'E')){
95        uint32_t size, fsize;
96        c->has_sound = 1;
97        size = get_be32(pb);
98        c->vidpos = url_ftell(pb) + size;
99        url_fskip(pb, 16);
100        fsize = get_le32(pb);
101
102        ast = av_new_stream(s, 0);
103        if (!ast)
104            return -1;
105        ff_get_wav_header(pb, ast->codec, fsize);
106        // find 'data' chunk
107        while(url_ftell(pb) < c->vidpos && !url_feof(pb)){
108            tag = get_le32(pb);
109            fsize = get_le32(pb);
110            if(tag == MKTAG('d', 'a', 't', 'a')) break;
111            url_fskip(pb, fsize);
112        }
113        c->bpc = (fsize + c->frames - 1) / c->frames;
114        if(ast->codec->block_align)
115            c->bpc = ((c->bpc + ast->codec->block_align - 1) / ast->codec->block_align) * ast->codec->block_align;
116        c->bytes_left = fsize;
117        c->wavpos = url_ftell(pb);
118        url_fseek(pb, c->vidpos, SEEK_SET);
119    }
120
121    /* now we are ready: build format streams */
122    st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
123    st->codec->codec_id   = CODEC_ID_DXA;
124    st->codec->width      = w;
125    st->codec->height     = h;
126    av_reduce(&den, &num, den, num, (1UL<<31)-1);
127    av_set_pts_info(st, 33, num, den);
128    /* flags & 0x80 means that image is interlaced,
129     * flags & 0x40 means that image has double height
130     * either way set true height
131     */
132    if(flags & 0xC0){
133        st->codec->height >>= 1;
134    }
135    c->readvid = !c->has_sound;
136    c->vidpos  = url_ftell(pb);
137    s->start_time = 0;
138    s->duration = (int64_t)c->frames * AV_TIME_BASE * num / den;
139    av_log(s, AV_LOG_DEBUG, "%d frame(s)\n",c->frames);
140
141    return 0;
142}
143
144static int dxa_read_packet(AVFormatContext *s, AVPacket *pkt)
145{
146    DXAContext *c = s->priv_data;
147    int ret;
148    uint32_t size;
149    uint8_t buf[DXA_EXTRA_SIZE], pal[768+4];
150    int pal_size = 0;
151
152    if(!c->readvid && c->has_sound && c->bytes_left){
153        c->readvid = 1;
154        url_fseek(s->pb, c->wavpos, SEEK_SET);
155        size = FFMIN(c->bytes_left, c->bpc);
156        ret = av_get_packet(s->pb, pkt, size);
157        pkt->stream_index = 1;
158        if(ret != size)
159            return AVERROR(EIO);
160        c->bytes_left -= size;
161        c->wavpos = url_ftell(s->pb);
162        return 0;
163    }
164    url_fseek(s->pb, c->vidpos, SEEK_SET);
165    while(!url_feof(s->pb) && c->frames){
166        get_buffer(s->pb, buf, 4);
167        switch(AV_RL32(buf)){
168        case MKTAG('N', 'U', 'L', 'L'):
169            if(av_new_packet(pkt, 4 + pal_size) < 0)
170                return AVERROR(ENOMEM);
171            pkt->stream_index = 0;
172            if(pal_size) memcpy(pkt->data, pal, pal_size);
173            memcpy(pkt->data + pal_size, buf, 4);
174            c->frames--;
175            c->vidpos = url_ftell(s->pb);
176            c->readvid = 0;
177            return 0;
178        case MKTAG('C', 'M', 'A', 'P'):
179            pal_size = 768+4;
180            memcpy(pal, buf, 4);
181            get_buffer(s->pb, pal + 4, 768);
182            break;
183        case MKTAG('F', 'R', 'A', 'M'):
184            get_buffer(s->pb, buf + 4, DXA_EXTRA_SIZE - 4);
185            size = AV_RB32(buf + 5);
186            if(size > 0xFFFFFF){
187                av_log(s, AV_LOG_ERROR, "Frame size is too big: %d\n", size);
188                return -1;
189            }
190            if(av_new_packet(pkt, size + DXA_EXTRA_SIZE + pal_size) < 0)
191                return AVERROR(ENOMEM);
192            memcpy(pkt->data + pal_size, buf, DXA_EXTRA_SIZE);
193            ret = get_buffer(s->pb, pkt->data + DXA_EXTRA_SIZE + pal_size, size);
194            if(ret != size){
195                av_free_packet(pkt);
196                return AVERROR(EIO);
197            }
198            if(pal_size) memcpy(pkt->data, pal, pal_size);
199            pkt->stream_index = 0;
200            c->frames--;
201            c->vidpos = url_ftell(s->pb);
202            c->readvid = 0;
203            return 0;
204        default:
205            av_log(s, AV_LOG_ERROR, "Unknown tag %c%c%c%c\n", buf[0], buf[1], buf[2], buf[3]);
206            return -1;
207        }
208    }
209    return AVERROR(EIO);
210}
211
212AVInputFormat dxa_demuxer = {
213    "dxa",
214    NULL_IF_CONFIG_SMALL("DXA"),
215    sizeof(DXAContext),
216    dxa_probe,
217    dxa_read_header,
218    dxa_read_packet,
219};
220