Libav
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00001 /* 00002 * ADX ADPCM codecs 00003 * Copyright (c) 2001,2003 BERO 00004 * 00005 * This file is part of FFmpeg. 00006 * 00007 * FFmpeg is free software; you can redistribute it and/or 00008 * modify it under the terms of the GNU Lesser General Public 00009 * License as published by the Free Software Foundation; either 00010 * version 2.1 of the License, or (at your option) any later version. 00011 * 00012 * FFmpeg is distributed in the hope that it will be useful, 00013 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 00015 * Lesser General Public License for more details. 00016 * 00017 * You should have received a copy of the GNU Lesser General Public 00018 * License along with FFmpeg; if not, write to the Free Software 00019 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 00020 */ 00021 00022 #include "libavutil/intreadwrite.h" 00023 #include "avcodec.h" 00024 #include "adx.h" 00025 00035 /* 18 bytes <-> 32 samples */ 00036 00037 static void adx_encode(unsigned char *adx,const short *wav,PREV *prev) 00038 { 00039 int scale; 00040 int i; 00041 int s0,s1,s2,d; 00042 int max=0; 00043 int min=0; 00044 int data[32]; 00045 00046 s1 = prev->s1; 00047 s2 = prev->s2; 00048 for(i=0;i<32;i++) { 00049 s0 = wav[i]; 00050 d = ((s0<<14) - SCALE1*s1 + SCALE2*s2)/BASEVOL; 00051 data[i]=d; 00052 if (max<d) max=d; 00053 if (min>d) min=d; 00054 s2 = s1; 00055 s1 = s0; 00056 } 00057 prev->s1 = s1; 00058 prev->s2 = s2; 00059 00060 /* -8..+7 */ 00061 00062 if (max==0 && min==0) { 00063 memset(adx,0,18); 00064 return; 00065 } 00066 00067 if (max/7>-min/8) scale = max/7; 00068 else scale = -min/8; 00069 00070 if (scale==0) scale=1; 00071 00072 AV_WB16(adx, scale); 00073 00074 for(i=0;i<16;i++) { 00075 adx[i+2] = ((data[i*2]/scale)<<4) | ((data[i*2+1]/scale)&0xf); 00076 } 00077 } 00078 00079 static int adx_encode_header(AVCodecContext *avctx,unsigned char *buf,size_t bufsize) 00080 { 00081 #if 0 00082 struct { 00083 uint32_t offset; /* 0x80000000 + sample start - 4 */ 00084 unsigned char unknown1[3]; /* 03 12 04 */ 00085 unsigned char channel; /* 1 or 2 */ 00086 uint32_t freq; 00087 uint32_t size; 00088 uint32_t unknown2; /* 01 f4 03 00 */ 00089 uint32_t unknown3; /* 00 00 00 00 */ 00090 uint32_t unknown4; /* 00 00 00 00 */ 00091 00092 /* if loop 00093 unknown3 00 15 00 01 00094 unknown4 00 00 00 01 00095 long loop_start_sample; 00096 long loop_start_byte; 00097 long loop_end_sample; 00098 long loop_end_byte; 00099 long 00100 */ 00101 } adxhdr; /* big endian */ 00102 /* offset-6 "(c)CRI" */ 00103 #endif 00104 AV_WB32(buf+0x00,0x80000000|0x20); 00105 AV_WB32(buf+0x04,0x03120400|avctx->channels); 00106 AV_WB32(buf+0x08,avctx->sample_rate); 00107 AV_WB32(buf+0x0c,0); /* FIXME: set after */ 00108 AV_WB32(buf+0x10,0x01040300); 00109 AV_WB32(buf+0x14,0x00000000); 00110 AV_WB32(buf+0x18,0x00000000); 00111 memcpy(buf+0x1c,"\0\0(c)CRI",8); 00112 return 0x20+4; 00113 } 00114 00115 static av_cold int adx_encode_init(AVCodecContext *avctx) 00116 { 00117 if (avctx->channels > 2) 00118 return -1; /* only stereo or mono =) */ 00119 avctx->frame_size = 32; 00120 00121 avctx->coded_frame= avcodec_alloc_frame(); 00122 avctx->coded_frame->key_frame= 1; 00123 00124 // avctx->bit_rate = avctx->sample_rate*avctx->channels*18*8/32; 00125 00126 av_log(avctx, AV_LOG_DEBUG, "adx encode init\n"); 00127 00128 return 0; 00129 } 00130 00131 static av_cold int adx_encode_close(AVCodecContext *avctx) 00132 { 00133 av_freep(&avctx->coded_frame); 00134 00135 return 0; 00136 } 00137 00138 static int adx_encode_frame(AVCodecContext *avctx, 00139 uint8_t *frame, int buf_size, void *data) 00140 { 00141 ADXContext *c = avctx->priv_data; 00142 const short *samples = data; 00143 unsigned char *dst = frame; 00144 int rest = avctx->frame_size; 00145 00146 /* 00147 input data size = 00148 ffmpeg.c: do_audio_out() 00149 frame_bytes = enc->frame_size * 2 * enc->channels; 00150 */ 00151 00152 // printf("sz=%d ",buf_size); fflush(stdout); 00153 if (!c->header_parsed) { 00154 int hdrsize = adx_encode_header(avctx,dst,buf_size); 00155 dst+=hdrsize; 00156 c->header_parsed = 1; 00157 } 00158 00159 if (avctx->channels==1) { 00160 while(rest>=32) { 00161 adx_encode(dst,samples,c->prev); 00162 dst+=18; 00163 samples+=32; 00164 rest-=32; 00165 } 00166 } else { 00167 while(rest>=32*2) { 00168 short tmpbuf[32*2]; 00169 int i; 00170 00171 for(i=0;i<32;i++) { 00172 tmpbuf[i] = samples[i*2]; 00173 tmpbuf[i+32] = samples[i*2+1]; 00174 } 00175 00176 adx_encode(dst,tmpbuf,c->prev); 00177 adx_encode(dst+18,tmpbuf+32,c->prev+1); 00178 dst+=18*2; 00179 samples+=32*2; 00180 rest-=32*2; 00181 } 00182 } 00183 return dst-frame; 00184 } 00185 00186 AVCodec adpcm_adx_encoder = { 00187 "adpcm_adx", 00188 AVMEDIA_TYPE_AUDIO, 00189 CODEC_ID_ADPCM_ADX, 00190 sizeof(ADXContext), 00191 adx_encode_init, 00192 adx_encode_frame, 00193 adx_encode_close, 00194 NULL, 00195 .sample_fmts = (const enum SampleFormat[]){SAMPLE_FMT_S16,SAMPLE_FMT_NONE}, 00196 .long_name = NULL_IF_CONFIG_SMALL("SEGA CRI ADX ADPCM"), 00197 };