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
26typedef struct avs_format {
27    VocDecContext 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} AvsFormat;
38
39typedef enum avs_block_type {
40    AVS_NONE      = 0x00,
41    AVS_VIDEO     = 0x01,
42    AVS_AUDIO     = 0x02,
43    AVS_PALETTE   = 0x03,
44    AVS_GAME_DATA = 0x04,
45} AvsBlockType;
46
47static int avs_probe(AVProbeData * p)
48{
49    const uint8_t *d;
50
51    d = p->buf;
52    if (d[0] == 'w' && d[1] == 'W' && d[2] == 0x10 && d[3] == 0)
53        /* Ensure the buffer probe scores higher than the extension probe.
54         * This avoids problems with misdetection as AviSynth scripts. */
55        return AVPROBE_SCORE_EXTENSION + 5;
56
57    return 0;
58}
59
60static int avs_read_header(AVFormatContext * s)
61{
62    AvsFormat *avs = s->priv_data;
63
64    s->ctx_flags |= AVFMTCTX_NOHEADER;
65
66    avio_skip(s->pb, 4);
67    avs->width = avio_rl16(s->pb);
68    avs->height = avio_rl16(s->pb);
69    avs->bits_per_sample = avio_rl16(s->pb);
70    avs->fps = avio_rl16(s->pb);
71    avs->nb_frames = avio_rl32(s->pb);
72    avs->remaining_frame_size = 0;
73    avs->remaining_audio_size = 0;
74
75    avs->st_video = avs->st_audio = NULL;
76
77    if (avs->width != 318 || avs->height != 198)
78        av_log(s, AV_LOG_ERROR, "This avs pretend to be %dx%d "
79               "when the avs format is supposed to be 318x198 only.\n",
80               avs->width, avs->height);
81
82    return 0;
83}
84
85static int
86avs_read_video_packet(AVFormatContext * s, AVPacket * pkt,
87                      AvsBlockType type, int sub_type, int size,
88                      uint8_t * palette, int palette_size)
89{
90    AvsFormat *avs = s->priv_data;
91    int ret;
92
93    ret = av_new_packet(pkt, size + palette_size);
94    if (ret < 0)
95        return ret;
96
97    if (palette_size) {
98        pkt->data[0] = 0x00;
99        pkt->data[1] = 0x03;
100        pkt->data[2] = palette_size & 0xFF;
101        pkt->data[3] = (palette_size >> 8) & 0xFF;
102        memcpy(pkt->data + 4, palette, palette_size - 4);
103    }
104
105    pkt->data[palette_size + 0] = sub_type;
106    pkt->data[palette_size + 1] = type;
107    pkt->data[palette_size + 2] = size & 0xFF;
108    pkt->data[palette_size + 3] = (size >> 8) & 0xFF;
109    ret = avio_read(s->pb, pkt->data + palette_size + 4, size - 4) + 4;
110    if (ret < size) {
111        av_free_packet(pkt);
112        return AVERROR(EIO);
113    }
114
115    pkt->size = ret + palette_size;
116    pkt->stream_index = avs->st_video->index;
117    if (sub_type == 0)
118        pkt->flags |= AV_PKT_FLAG_KEY;
119
120    return 0;
121}
122
123static int avs_read_audio_packet(AVFormatContext * s, AVPacket * pkt)
124{
125    AvsFormat *avs = s->priv_data;
126    int ret, size;
127
128    size = avio_tell(s->pb);
129    ret = ff_voc_get_packet(s, pkt, avs->st_audio, avs->remaining_audio_size);
130    size = avio_tell(s->pb) - size;
131    avs->remaining_audio_size -= size;
132
133    if (ret == AVERROR(EIO))
134        return 0;    /* this indicate EOS */
135    if (ret < 0)
136        return ret;
137
138    pkt->stream_index = avs->st_audio->index;
139    pkt->flags |= AV_PKT_FLAG_KEY;
140
141    return size;
142}
143
144static int avs_read_packet(AVFormatContext * s, AVPacket * pkt)
145{
146    AvsFormat *avs = s->priv_data;
147    int sub_type = 0, size = 0;
148    AvsBlockType type = AVS_NONE;
149    int palette_size = 0;
150    uint8_t palette[4 + 3 * 256];
151    int ret;
152
153    if (avs->remaining_audio_size > 0)
154        if (avs_read_audio_packet(s, pkt) > 0)
155            return 0;
156
157    while (1) {
158        if (avs->remaining_frame_size <= 0) {
159            if (!avio_rl16(s->pb))    /* found EOF */
160                return AVERROR(EIO);
161            avs->remaining_frame_size = avio_rl16(s->pb) - 4;
162        }
163
164        while (avs->remaining_frame_size > 0) {
165            sub_type = avio_r8(s->pb);
166            type = avio_r8(s->pb);
167            size = avio_rl16(s->pb);
168            if (size < 4)
169                return AVERROR_INVALIDDATA;
170            avs->remaining_frame_size -= size;
171
172            switch (type) {
173            case AVS_PALETTE:
174                if (size - 4 > sizeof(palette))
175                    return AVERROR_INVALIDDATA;
176                ret = avio_read(s->pb, palette, size - 4);
177                if (ret < size - 4)
178                    return AVERROR(EIO);
179                palette_size = size;
180                break;
181
182            case AVS_VIDEO:
183                if (!avs->st_video) {
184                    avs->st_video = avformat_new_stream(s, NULL);
185                    if (avs->st_video == NULL)
186                        return AVERROR(ENOMEM);
187                    avs->st_video->codec->codec_type = AVMEDIA_TYPE_VIDEO;
188                    avs->st_video->codec->codec_id = AV_CODEC_ID_AVS;
189                    avs->st_video->codec->width = avs->width;
190                    avs->st_video->codec->height = avs->height;
191                    avs->st_video->codec->bits_per_coded_sample=avs->bits_per_sample;
192                    avs->st_video->nb_frames = avs->nb_frames;
193#if FF_API_R_FRAME_RATE
194                    avs->st_video->r_frame_rate =
195#endif
196                    avs->st_video->avg_frame_rate = (AVRational){avs->fps, 1};
197                }
198                return avs_read_video_packet(s, pkt, type, sub_type, size,
199                                             palette, palette_size);
200
201            case AVS_AUDIO:
202                if (!avs->st_audio) {
203                    avs->st_audio = avformat_new_stream(s, NULL);
204                    if (avs->st_audio == NULL)
205                        return AVERROR(ENOMEM);
206                    avs->st_audio->codec->codec_type = AVMEDIA_TYPE_AUDIO;
207                }
208                avs->remaining_audio_size = size - 4;
209                size = avs_read_audio_packet(s, pkt);
210                if (size != 0)
211                    return size;
212                break;
213
214            default:
215                avio_skip(s->pb, size - 4);
216            }
217        }
218    }
219}
220
221static int avs_read_close(AVFormatContext * s)
222{
223    return 0;
224}
225
226AVInputFormat ff_avs_demuxer = {
227    .name           = "avs",
228    .long_name      = NULL_IF_CONFIG_SMALL("AVS"),
229    .priv_data_size = sizeof(AvsFormat),
230    .read_probe     = avs_probe,
231    .read_header    = avs_read_header,
232    .read_packet    = avs_read_packet,
233    .read_close     = avs_read_close,
234};
235