04e9b789b5422a9f1c593da72a52501f5529d8d5
[libav.git] / libavcodec / adxenc.c
1 /*
2 * ADX ADPCM codecs
3 * Copyright (c) 2001,2003 BERO
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 "avcodec.h"
24 #include "adx.h"
25
26 /**
27 * @file libavcodec/adxenc.c
28 * SEGA CRI adx codecs.
29 *
30 * Reference documents:
31 * http://ku-www.ss.titech.ac.jp/~yatsushi/adx.html
32 * adx2wav & wav2adx http://www.geocities.co.jp/Playtown/2004/
33 */
34
35 /* 18 bytes <-> 32 samples */
36
37 static void adx_encode(unsigned char *adx,const short *wav,PREV *prev)
38 {
39 int scale;
40 int i;
41 int s0,s1,s2,d;
42 int max=0;
43 int min=0;
44 int data[32];
45
46 s1 = prev->s1;
47 s2 = prev->s2;
48 for(i=0;i<32;i++) {
49 s0 = wav[i];
50 d = ((s0<<14) - SCALE1*s1 + SCALE2*s2)/BASEVOL;
51 data[i]=d;
52 if (max<d) max=d;
53 if (min>d) min=d;
54 s2 = s1;
55 s1 = s0;
56 }
57 prev->s1 = s1;
58 prev->s2 = s2;
59
60 /* -8..+7 */
61
62 if (max==0 && min==0) {
63 memset(adx,0,18);
64 return;
65 }
66
67 if (max/7>-min/8) scale = max/7;
68 else scale = -min/8;
69
70 if (scale==0) scale=1;
71
72 AV_WB16(adx, scale);
73
74 for(i=0;i<16;i++) {
75 adx[i+2] = ((data[i*2]/scale)<<4) | ((data[i*2+1]/scale)&0xf);
76 }
77 }
78
79 static int adx_encode_header(AVCodecContext *avctx,unsigned char *buf,size_t bufsize)
80 {
81 #if 0
82 struct {
83 uint32_t offset; /* 0x80000000 + sample start - 4 */
84 unsigned char unknown1[3]; /* 03 12 04 */
85 unsigned char channel; /* 1 or 2 */
86 uint32_t freq;
87 uint32_t size;
88 uint32_t unknown2; /* 01 f4 03 00 */
89 uint32_t unknown3; /* 00 00 00 00 */
90 uint32_t unknown4; /* 00 00 00 00 */
91
92 /* if loop
93 unknown3 00 15 00 01
94 unknown4 00 00 00 01
95 long loop_start_sample;
96 long loop_start_byte;
97 long loop_end_sample;
98 long loop_end_byte;
99 long
100 */
101 } adxhdr; /* big endian */
102 /* offset-6 "(c)CRI" */
103 #endif
104 AV_WB32(buf+0x00,0x80000000|0x20);
105 AV_WB32(buf+0x04,0x03120400|avctx->channels);
106 AV_WB32(buf+0x08,avctx->sample_rate);
107 AV_WB32(buf+0x0c,0); /* FIXME: set after */
108 AV_WB32(buf+0x10,0x01040300);
109 AV_WB32(buf+0x14,0x00000000);
110 AV_WB32(buf+0x18,0x00000000);
111 memcpy(buf+0x1c,"\0\0(c)CRI",8);
112 return 0x20+4;
113 }
114
115 static av_cold int adx_encode_init(AVCodecContext *avctx)
116 {
117 if (avctx->channels > 2)
118 return -1; /* only stereo or mono =) */
119 avctx->frame_size = 32;
120
121 avctx->coded_frame= avcodec_alloc_frame();
122 avctx->coded_frame->key_frame= 1;
123
124 // avctx->bit_rate = avctx->sample_rate*avctx->channels*18*8/32;
125
126 av_log(avctx, AV_LOG_DEBUG, "adx encode init\n");
127
128 return 0;
129 }
130
131 static av_cold int adx_encode_close(AVCodecContext *avctx)
132 {
133 av_freep(&avctx->coded_frame);
134
135 return 0;
136 }
137
138 static int adx_encode_frame(AVCodecContext *avctx,
139 uint8_t *frame, int buf_size, void *data)
140 {
141 ADXContext *c = avctx->priv_data;
142 const short *samples = data;
143 unsigned char *dst = frame;
144 int rest = avctx->frame_size;
145
146 /*
147 input data size =
148 ffmpeg.c: do_audio_out()
149 frame_bytes = enc->frame_size * 2 * enc->channels;
150 */
151
152 // printf("sz=%d ",buf_size); fflush(stdout);
153 if (!c->header_parsed) {
154 int hdrsize = adx_encode_header(avctx,dst,buf_size);
155 dst+=hdrsize;
156 c->header_parsed = 1;
157 }
158
159 if (avctx->channels==1) {
160 while(rest>=32) {
161 adx_encode(dst,samples,c->prev);
162 dst+=18;
163 samples+=32;
164 rest-=32;
165 }
166 } else {
167 while(rest>=32*2) {
168 short tmpbuf[32*2];
169 int i;
170
171 for(i=0;i<32;i++) {
172 tmpbuf[i] = samples[i*2];
173 tmpbuf[i+32] = samples[i*2+1];
174 }
175
176 adx_encode(dst,tmpbuf,c->prev);
177 adx_encode(dst+18,tmpbuf+32,c->prev+1);
178 dst+=18*2;
179 samples+=32*2;
180 rest-=32*2;
181 }
182 }
183 return dst-frame;
184 }
185
186 AVCodec adpcm_adx_encoder = {
187 "adpcm_adx",
188 CODEC_TYPE_AUDIO,
189 CODEC_ID_ADPCM_ADX,
190 sizeof(ADXContext),
191 adx_encode_init,
192 adx_encode_frame,
193 adx_encode_close,
194 NULL,
195 .sample_fmts = (const enum SampleFormat[]){SAMPLE_FMT_S16,SAMPLE_FMT_NONE},
196 .long_name = NULL_IF_CONFIG_SMALL("SEGA CRI ADX ADPCM"),
197 };