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 /**
23  * @file
24  * Argonaut Games' Creature Shock demuxer
25  * @see http://wiki.multimedia.cx/index.php?title=AVS
26  */
27 
28 #include "avformat.h"
29 #include "voc.h"
30 
31 
32 typedef struct avs_format {
33     VocDecContext voc;
34     AVStream *st_video;
35     AVStream *st_audio;
36     int width;
37     int height;
38     int bits_per_sample;
39     int fps;
40     int nb_frames;
41     int remaining_frame_size;
42     int remaining_audio_size;
43 } AvsFormat;
44 
45 typedef enum avs_block_type {
46     AVS_NONE      = 0x00,
47     AVS_VIDEO     = 0x01,
48     AVS_AUDIO     = 0x02,
49     AVS_PALETTE   = 0x03,
50     AVS_GAME_DATA = 0x04,
51 } AvsBlockType;
52 
avs_probe(const AVProbeData * p)53 static int avs_probe(const AVProbeData * p)
54 {
55     const uint8_t *d;
56 
57     d = p->buf;
58     if (d[0] == 'w' && d[1] == 'W' && d[2] == 0x10 && d[3] == 0)
59         /* Ensure the buffer probe scores higher than the extension probe.
60          * This avoids problems with misdetection as AviSynth scripts. */
61         return AVPROBE_SCORE_EXTENSION + 5;
62 
63     return 0;
64 }
65 
avs_read_header(AVFormatContext * s)66 static int avs_read_header(AVFormatContext * s)
67 {
68     AvsFormat *avs = s->priv_data;
69 
70     s->ctx_flags |= AVFMTCTX_NOHEADER;
71 
72     avio_skip(s->pb, 4);
73     avs->width = avio_rl16(s->pb);
74     avs->height = avio_rl16(s->pb);
75     avs->bits_per_sample = avio_rl16(s->pb);
76     avs->fps = avio_rl16(s->pb);
77     avs->nb_frames = avio_rl32(s->pb);
78     avs->remaining_frame_size = 0;
79     avs->remaining_audio_size = 0;
80 
81     avs->st_video = avs->st_audio = NULL;
82 
83     if (avs->width != 318 || avs->height != 198)
84         av_log(s, AV_LOG_ERROR, "This avs pretend to be %dx%d "
85                "when the avs format is supposed to be 318x198 only.\n",
86                avs->width, avs->height);
87 
88     return 0;
89 }
90 
91 static int
avs_read_video_packet(AVFormatContext * s,AVPacket * pkt,AvsBlockType type,int sub_type,int size,uint8_t * palette,int palette_size)92 avs_read_video_packet(AVFormatContext * s, AVPacket * pkt,
93                       AvsBlockType type, int sub_type, int size,
94                       uint8_t * palette, int palette_size)
95 {
96     AvsFormat *avs = s->priv_data;
97     int ret;
98 
99     ret = av_new_packet(pkt, size + palette_size);
100     if (ret < 0)
101         return ret;
102 
103     if (palette_size) {
104         pkt->data[0] = 0x00;
105         pkt->data[1] = 0x03;
106         pkt->data[2] = palette_size & 0xFF;
107         pkt->data[3] = (palette_size >> 8) & 0xFF;
108         memcpy(pkt->data + 4, palette, palette_size - 4);
109     }
110 
111     pkt->data[palette_size + 0] = sub_type;
112     pkt->data[palette_size + 1] = type;
113     pkt->data[palette_size + 2] = size & 0xFF;
114     pkt->data[palette_size + 3] = (size >> 8) & 0xFF;
115     ret = avio_read(s->pb, pkt->data + palette_size + 4, size - 4) + 4;
116     if (ret < size) {
117         return AVERROR(EIO);
118     }
119 
120     pkt->size = ret + palette_size;
121     pkt->stream_index = avs->st_video->index;
122     if (sub_type == 0)
123         pkt->flags |= AV_PKT_FLAG_KEY;
124 
125     return 0;
126 }
127 
avs_read_audio_packet(AVFormatContext * s,AVPacket * pkt)128 static int avs_read_audio_packet(AVFormatContext * s, AVPacket * pkt)
129 {
130     AvsFormat *avs = s->priv_data;
131     int ret, size;
132 
133     size = avio_tell(s->pb);
134     ret = ff_voc_get_packet(s, pkt, avs->st_audio, avs->remaining_audio_size);
135     size = avio_tell(s->pb) - size;
136     avs->remaining_audio_size -= size;
137 
138     if (ret == AVERROR(EIO))
139         return 0;    /* this indicate EOS */
140     if (ret < 0)
141         return ret;
142 
143     pkt->stream_index = avs->st_audio->index;
144     pkt->flags |= AV_PKT_FLAG_KEY;
145 
146     return size;
147 }
148 
avs_read_packet(AVFormatContext * s,AVPacket * pkt)149 static int avs_read_packet(AVFormatContext * s, AVPacket * pkt)
150 {
151     AvsFormat *avs = s->priv_data;
152     int sub_type = 0, size = 0;
153     AvsBlockType type = AVS_NONE;
154     int palette_size = 0;
155     uint8_t palette[4 + 3 * 256];
156     int ret;
157 
158     if (avs->remaining_audio_size > 0)
159         if (avs_read_audio_packet(s, pkt) > 0)
160             return 0;
161 
162     while (1) {
163         if (avs->remaining_frame_size <= 0) {
164             if (!avio_rl16(s->pb))    /* found EOF */
165                 return AVERROR(EIO);
166             avs->remaining_frame_size = avio_rl16(s->pb) - 4;
167         }
168 
169         while (avs->remaining_frame_size > 0) {
170             sub_type = avio_r8(s->pb);
171             type = avio_r8(s->pb);
172             size = avio_rl16(s->pb);
173             if (size < 4)
174                 return AVERROR_INVALIDDATA;
175             avs->remaining_frame_size -= size;
176 
177             switch (type) {
178             case AVS_PALETTE:
179                 if (size - 4 > sizeof(palette))
180                     return AVERROR_INVALIDDATA;
181                 ret = avio_read(s->pb, palette, size - 4);
182                 if (ret < size - 4)
183                     return AVERROR(EIO);
184                 palette_size = size;
185                 break;
186 
187             case AVS_VIDEO:
188                 if (!avs->st_video) {
189                     avs->st_video = avformat_new_stream(s, NULL);
190                     if (!avs->st_video)
191                         return AVERROR(ENOMEM);
192                     avs->st_video->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
193                     avs->st_video->codecpar->codec_id = AV_CODEC_ID_AVS;
194                     avs->st_video->codecpar->width = avs->width;
195                     avs->st_video->codecpar->height = avs->height;
196                     avs->st_video->codecpar->bits_per_coded_sample=avs->bits_per_sample;
197                     avs->st_video->nb_frames = avs->nb_frames;
198 #if FF_API_R_FRAME_RATE
199                     avs->st_video->r_frame_rate =
200 #endif
201                     avs->st_video->avg_frame_rate = (AVRational){avs->fps, 1};
202                 }
203                 return avs_read_video_packet(s, pkt, type, sub_type, size,
204                                              palette, palette_size);
205 
206             case AVS_AUDIO:
207                 if (!avs->st_audio) {
208                     avs->st_audio = avformat_new_stream(s, NULL);
209                     if (!avs->st_audio)
210                         return AVERROR(ENOMEM);
211                     avs->st_audio->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
212                 }
213                 avs->remaining_audio_size = size - 4;
214                 size = avs_read_audio_packet(s, pkt);
215                 if (size != 0)
216                     return size;
217                 break;
218 
219             default:
220                 avio_skip(s->pb, size - 4);
221             }
222         }
223     }
224 }
225 
226 AVInputFormat ff_avs_demuxer = {
227     .name           = "avs",
228     .long_name      = NULL_IF_CONFIG_SMALL("Argonaut Games Creature Shock"),
229     .priv_data_size = sizeof(AvsFormat),
230     .read_probe     = avs_probe,
231     .read_header    = avs_read_header,
232     .read_packet    = avs_read_packet,
233 };
234