Statistics
| Branch: | Revision:

ffmpeg / libavformat / avs.c @ 0ab1ebea

History | View | Annotate | Download (6.46 KB)

1
/*
2
 * AVS demuxer.
3
 * Copyright (c) 2006  Aurelien Jacobs <aurel@gnuage.org>
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 "avformat.h"
23
#include "voc.h"
24

    
25

    
26
typedef struct avs_format {
27
    voc_dec_context_t voc;
28
    AVStream *st_video;
29
    AVStream *st_audio;
30
    int width;
31
    int height;
32
    int bits_per_sample;
33
    int fps;
34
    int nb_frames;
35
    int remaining_frame_size;
36
    int remaining_audio_size;
37
} avs_format_t;
38

    
39
typedef enum avs_block_type {
40
    AVS_VIDEO     = 0x01,
41
    AVS_AUDIO     = 0x02,
42
    AVS_PALETTE   = 0x03,
43
    AVS_GAME_DATA = 0x04,
44
} avs_block_type_t;
45

    
46
static int avs_probe(AVProbeData * p)
47
{
48
    const uint8_t *d;
49

    
50
    d = p->buf;
51
    if (d[0] == 'w' && d[1] == 'W' && d[2] == 0x10 && d[3] == 0)
52
        return 50;
53

    
54
    return 0;
55
}
56

    
57
static int avs_read_header(AVFormatContext * s, AVFormatParameters * ap)
58
{
59
    avs_format_t *avs = s->priv_data;
60

    
61
    s->ctx_flags |= AVFMTCTX_NOHEADER;
62

    
63
    url_fskip(&s->pb, 4);
64
    avs->width = get_le16(&s->pb);
65
    avs->height = get_le16(&s->pb);
66
    avs->bits_per_sample = get_le16(&s->pb);
67
    avs->fps = get_le16(&s->pb);
68
    avs->nb_frames = get_le32(&s->pb);
69
    avs->remaining_frame_size = 0;
70
    avs->remaining_audio_size = 0;
71

    
72
    avs->st_video = avs->st_audio = NULL;
73

    
74
    if (avs->width != 318 || avs->height != 198)
75
        av_log(s, AV_LOG_ERROR, "This avs pretend to be %dx%d "
76
               "when the avs format is supposed to be 318x198 only.\n",
77
               avs->width, avs->height);
78

    
79
    return 0;
80
}
81

    
82
static int
83
avs_read_video_packet(AVFormatContext * s, AVPacket * pkt,
84
                      avs_block_type_t type, int sub_type, int size,
85
                      uint8_t * palette, int palette_size)
86
{
87
    avs_format_t *avs = s->priv_data;
88
    int ret;
89

    
90
    ret = av_new_packet(pkt, size + palette_size);
91
    if (ret < 0)
92
        return ret;
93

    
94
    if (palette_size) {
95
        pkt->data[0] = 0x00;
96
        pkt->data[1] = 0x03;
97
        pkt->data[2] = palette_size & 0xFF;
98
        pkt->data[3] = (palette_size >> 8) & 0xFF;
99
        memcpy(pkt->data + 4, palette, palette_size - 4);
100
    }
101

    
102
    pkt->data[palette_size + 0] = sub_type;
103
    pkt->data[palette_size + 1] = type;
104
    pkt->data[palette_size + 2] = size & 0xFF;
105
    pkt->data[palette_size + 3] = (size >> 8) & 0xFF;
106
    ret = get_buffer(&s->pb, pkt->data + palette_size + 4, size - 4) + 4;
107
    if (ret < size) {
108
        av_free_packet(pkt);
109
        return AVERROR(EIO);
110
    }
111

    
112
    pkt->size = ret + palette_size;
113
    pkt->stream_index = avs->st_video->index;
114
    if (sub_type == 0)
115
        pkt->flags |= PKT_FLAG_KEY;
116

    
117
    return 0;
118
}
119

    
120
static int avs_read_audio_packet(AVFormatContext * s, AVPacket * pkt)
121
{
122
    avs_format_t *avs = s->priv_data;
123
    int ret, size;
124

    
125
    size = url_ftell(&s->pb);
126
    ret = voc_get_packet(s, pkt, avs->st_audio, avs->remaining_audio_size);
127
    size = url_ftell(&s->pb) - size;
128
    avs->remaining_audio_size -= size;
129

    
130
    if (ret == AVERROR(EIO))
131
        return 0;    /* this indicate EOS */
132
    if (ret < 0)
133
        return ret;
134

    
135
    pkt->stream_index = avs->st_audio->index;
136
    pkt->flags |= PKT_FLAG_KEY;
137

    
138
    return size;
139
}
140

    
141
static int avs_read_packet(AVFormatContext * s, AVPacket * pkt)
142
{
143
    avs_format_t *avs = s->priv_data;
144
    int sub_type = 0, size = 0;
145
    avs_block_type_t type = 0;
146
    int palette_size = 0;
147
    uint8_t palette[4 + 3 * 256];
148
    int ret;
149

    
150
    if (avs->remaining_audio_size > 0)
151
        if (avs_read_audio_packet(s, pkt) > 0)
152
            return 0;
153

    
154
    while (1) {
155
        if (avs->remaining_frame_size <= 0) {
156
            if (!get_le16(&s->pb))    /* found EOF */
157
                return AVERROR(EIO);
158
            avs->remaining_frame_size = get_le16(&s->pb) - 4;
159
        }
160

    
161
        while (avs->remaining_frame_size > 0) {
162
            sub_type = get_byte(&s->pb);
163
            type = get_byte(&s->pb);
164
            size = get_le16(&s->pb);
165
            avs->remaining_frame_size -= size;
166

    
167
            switch (type) {
168
            case AVS_PALETTE:
169
                ret = get_buffer(&s->pb, palette, size - 4);
170
                if (ret < size - 4)
171
                    return AVERROR(EIO);
172
                palette_size = size;
173
                break;
174

    
175
            case AVS_VIDEO:
176
                if (!avs->st_video) {
177
                    avs->st_video = av_new_stream(s, AVS_VIDEO);
178
                    if (avs->st_video == NULL)
179
                        return AVERROR(ENOMEM);
180
                    avs->st_video->codec->codec_type = CODEC_TYPE_VIDEO;
181
                    avs->st_video->codec->codec_id = CODEC_ID_AVS;
182
                    avs->st_video->codec->width = avs->width;
183
                    avs->st_video->codec->height = avs->height;
184
                    avs->st_video->codec->bits_per_sample=avs->bits_per_sample;
185
                    avs->st_video->nb_frames = avs->nb_frames;
186
                    avs->st_video->codec->time_base = (AVRational) {
187
                    1, avs->fps};
188
                }
189
                return avs_read_video_packet(s, pkt, type, sub_type, size,
190
                                             palette, palette_size);
191

    
192
            case AVS_AUDIO:
193
                if (!avs->st_audio) {
194
                    avs->st_audio = av_new_stream(s, AVS_AUDIO);
195
                    if (avs->st_audio == NULL)
196
                        return AVERROR(ENOMEM);
197
                    avs->st_audio->codec->codec_type = CODEC_TYPE_AUDIO;
198
                }
199
                avs->remaining_audio_size = size - 4;
200
                size = avs_read_audio_packet(s, pkt);
201
                if (size != 0)
202
                    return size;
203
                break;
204

    
205
            default:
206
                url_fskip(&s->pb, size - 4);
207
            }
208
        }
209
    }
210
}
211

    
212
static int avs_read_close(AVFormatContext * s)
213
{
214
    return 0;
215
}
216

    
217
AVInputFormat avs_demuxer = {
218
    "avs",
219
    "avs format",
220
    sizeof(avs_format_t),
221
    avs_probe,
222
    avs_read_header,
223
    avs_read_packet,
224
    avs_read_close,
225
};