* ADX ADPCM codecs
* Copyright (c) 2001,2003 BERO
*
- * This file is part of FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
- * FFmpeg is distributed in the hope that it will be useful,
+ * Libav is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
- * License along with FFmpeg; if not, write to the Free Software
+ * License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/intreadwrite.h"
#include "avcodec.h"
#include "adx.h"
+#include "get_bits.h"
/**
* @file
static av_cold int adx_decode_init(AVCodecContext *avctx)
{
- avctx->sample_fmt = SAMPLE_FMT_S16;
+ ADXContext *c = avctx->priv_data;
+ int ret, header_size;
+
+ if (avctx->extradata_size >= 24) {
+ if ((ret = avpriv_adx_decode_header(avctx, avctx->extradata,
+ avctx->extradata_size, &header_size,
+ c->coeff)) < 0) {
+ av_log(avctx, AV_LOG_ERROR, "error parsing ADX header\n");
+ return AVERROR_INVALIDDATA;
+ }
+ c->channels = avctx->channels;
+ c->header_parsed = 1;
+ }
+
+ avctx->sample_fmt = AV_SAMPLE_FMT_S16P;
+
+ avcodec_get_frame_defaults(&c->frame);
+ avctx->coded_frame = &c->frame;
+
return 0;
}
-/* 18 bytes <-> 32 samples */
-
-static void adx_decode(short *out,const unsigned char *in,PREV *prev)
+/**
+ * Decode 32 samples from 18 bytes.
+ *
+ * A 16-bit scalar value is applied to 32 residuals, which then have a
+ * 2nd-order LPC filter applied to it to form the output signal for a single
+ * channel.
+ */
+static int adx_decode(ADXContext *c, int16_t *out, int offset,
+ const uint8_t *in, int ch)
{
+ ADXChannelState *prev = &c->prev[ch];
+ GetBitContext gb;
int scale = AV_RB16(in);
int i;
- int s0,s1,s2,d;
+ int s0, s1, s2, d;
-// printf("%x ",scale);
+ /* check if this is an EOF packet */
+ if (scale & 0x8000)
+ return -1;
- in+=2;
+ init_get_bits(&gb, in + 2, (BLOCK_SIZE - 2) * 8);
+ out += offset;
s1 = prev->s1;
s2 = prev->s2;
- for(i=0;i<16;i++) {
- d = in[i];
- // d>>=4; if (d&8) d-=16;
- d = ((signed char)d >> 4);
- s0 = (BASEVOL*d*scale + SCALE1*s1 - SCALE2*s2)>>14;
+ for (i = 0; i < BLOCK_SAMPLES; i++) {
+ d = get_sbits(&gb, 4);
+ s0 = ((d << COEFF_BITS) * scale + c->coeff[0] * s1 + c->coeff[1] * s2) >> COEFF_BITS;
s2 = s1;
s1 = av_clip_int16(s0);
- *out++=s1;
-
- d = in[i];
- //d&=15; if (d&8) d-=16;
- d = ((signed char)(d<<4) >> 4);
- s0 = (BASEVOL*d*scale + SCALE1*s1 - SCALE2*s2)>>14;
- s2 = s1;
- s1 = av_clip_int16(s0);
- *out++=s1;
+ *out++ = s1;
}
prev->s1 = s1;
prev->s2 = s2;
+ return 0;
}
-static void adx_decode_stereo(short *out,const unsigned char *in,PREV *prev)
+static int adx_decode_frame(AVCodecContext *avctx, void *data,
+ int *got_frame_ptr, AVPacket *avpkt)
{
- short tmp[32*2];
- int i;
-
- adx_decode(tmp ,in ,prev);
- adx_decode(tmp+32,in+18,prev+1);
- for(i=0;i<32;i++) {
- out[i*2] = tmp[i];
- out[i*2+1] = tmp[i+32];
+ int buf_size = avpkt->size;
+ ADXContext *c = avctx->priv_data;
+ int16_t **samples;
+ int samples_offset;
+ const uint8_t *buf = avpkt->data;
+ int num_blocks, ch, ret;
+
+ if (c->eof) {
+ *got_frame_ptr = 0;
+ return buf_size;
}
-}
-/* return data offset or 0 */
-static int adx_decode_header(AVCodecContext *avctx,const unsigned char *buf,size_t bufsize)
-{
- int offset;
+ if (!c->header_parsed && buf_size >= 2 && AV_RB16(buf) == 0x8000) {
+ int header_size;
+ if ((ret = avpriv_adx_decode_header(avctx, buf, buf_size, &header_size,
+ c->coeff)) < 0) {
+ av_log(avctx, AV_LOG_ERROR, "error parsing ADX header\n");
+ return AVERROR_INVALIDDATA;
+ }
+ c->channels = avctx->channels;
+ c->header_parsed = 1;
+ if (buf_size < header_size)
+ return AVERROR_INVALIDDATA;
+ buf += header_size;
+ buf_size -= header_size;
+ }
+ if (!c->header_parsed)
+ return AVERROR_INVALIDDATA;
+
+ /* calculate number of blocks in the packet */
+ num_blocks = buf_size / (BLOCK_SIZE * c->channels);
+
+ /* if the packet is not an even multiple of BLOCK_SIZE, check for an EOF
+ packet */
+ if (!num_blocks || buf_size % (BLOCK_SIZE * avctx->channels)) {
+ if (buf_size >= 4 && (AV_RB16(buf) & 0x8000)) {
+ c->eof = 1;
+ *got_frame_ptr = 0;
+ return avpkt->size;
+ }
+ return AVERROR_INVALIDDATA;
+ }
- if (buf[0]!=0x80) return 0;
- offset = (AV_RB32(buf)^0x80000000)+4;
- if (bufsize<offset || memcmp(buf+offset-6,"(c)CRI",6)) return 0;
+ /* get output buffer */
+ c->frame.nb_samples = num_blocks * BLOCK_SAMPLES;
+ if ((ret = avctx->get_buffer(avctx, &c->frame)) < 0) {
+ av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+ return ret;
+ }
+ samples = (int16_t **)c->frame.extended_data;
+ samples_offset = 0;
+
+ while (num_blocks--) {
+ for (ch = 0; ch < c->channels; ch++) {
+ if (adx_decode(c, samples[ch], samples_offset, buf, ch)) {
+ c->eof = 1;
+ buf = avpkt->data + avpkt->size;
+ break;
+ }
+ buf_size -= BLOCK_SIZE;
+ buf += BLOCK_SIZE;
+ }
+ samples_offset += BLOCK_SAMPLES;
+ }
- avctx->channels = buf[7];
- avctx->sample_rate = AV_RB32(buf+8);
- avctx->bit_rate = avctx->sample_rate*avctx->channels*18*8/32;
+ *got_frame_ptr = 1;
+ *(AVFrame *)data = c->frame;
- return offset;
+ return buf - avpkt->data;
}
-static int adx_decode_frame(AVCodecContext *avctx,
- void *data, int *data_size,
- AVPacket *avpkt)
+static void adx_decode_flush(AVCodecContext *avctx)
{
- const uint8_t *buf0 = avpkt->data;
- int buf_size = avpkt->size;
ADXContext *c = avctx->priv_data;
- short *samples = data;
- const uint8_t *buf = buf0;
- int rest = buf_size;
-
- if (!c->header_parsed) {
- int hdrsize = adx_decode_header(avctx,buf,rest);
- if (hdrsize==0) return -1;
- c->header_parsed = 1;
- buf += hdrsize;
- rest -= hdrsize;
- }
-
- /* 18 bytes of data are expanded into 32*2 bytes of audio,
- so guard against buffer overflows */
- if(rest/18 > *data_size/64)
- rest = (*data_size/64) * 18;
-
- if (c->in_temp) {
- int copysize = 18*avctx->channels - c->in_temp;
- memcpy(c->dec_temp+c->in_temp,buf,copysize);
- rest -= copysize;
- buf += copysize;
- if (avctx->channels==1) {
- adx_decode(samples,c->dec_temp,c->prev);
- samples += 32;
- } else {
- adx_decode_stereo(samples,c->dec_temp,c->prev);
- samples += 32*2;
- }
- }
- //
- if (avctx->channels==1) {
- while(rest>=18) {
- adx_decode(samples,buf,c->prev);
- rest-=18;
- buf+=18;
- samples+=32;
- }
- } else {
- while(rest>=18*2) {
- adx_decode_stereo(samples,buf,c->prev);
- rest-=18*2;
- buf+=18*2;
- samples+=32*2;
- }
- }
- //
- c->in_temp = rest;
- if (rest) {
- memcpy(c->dec_temp,buf,rest);
- buf+=rest;
- }
- *data_size = (uint8_t*)samples - (uint8_t*)data;
-// printf("%d:%d ",buf-buf0,*data_size); fflush(stdout);
- return buf-buf0;
+ memset(c->prev, 0, sizeof(c->prev));
+ c->eof = 0;
}
-AVCodec adpcm_adx_decoder = {
- "adpcm_adx",
- AVMEDIA_TYPE_AUDIO,
- CODEC_ID_ADPCM_ADX,
- sizeof(ADXContext),
- adx_decode_init,
- NULL,
- NULL,
- adx_decode_frame,
- .long_name = NULL_IF_CONFIG_SMALL("SEGA CRI ADX ADPCM"),
+AVCodec ff_adpcm_adx_decoder = {
+ .name = "adpcm_adx",
+ .type = AVMEDIA_TYPE_AUDIO,
+ .id = AV_CODEC_ID_ADPCM_ADX,
+ .priv_data_size = sizeof(ADXContext),
+ .init = adx_decode_init,
+ .decode = adx_decode_frame,
+ .flush = adx_decode_flush,
+ .capabilities = CODEC_CAP_DR1,
+ .long_name = NULL_IF_CONFIG_SMALL("SEGA CRI ADX ADPCM"),
+ .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
+ AV_SAMPLE_FMT_NONE },
};
-
projects / ffmpeg / blobdiff