#include "libavutil/intreadwrite.h"
#include "avcodec.h"
#include "adx.h"
+#include "get_bits.h"
/**
* @file
static av_cold int adx_decode_init(AVCodecContext *avctx)
{
+ 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_S16;
+
+ avcodec_get_frame_defaults(&c->frame);
+ avctx->coded_frame = &c->frame;
+
return 0;
}
* 2nd-order LPC filter applied to it to form the output signal for a single
* channel.
*/
-static void adx_decode(int16_t *out, const uint8_t *in, ADXChannelState *prev)
+static int adx_decode(ADXContext *c, int16_t *out, 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;
- in += 2;
+ /* check if this is an EOF packet */
+ if (scale & 0x8000)
+ return -1;
+
+ init_get_bits(&gb, in + 2, (BLOCK_SIZE - 2) * 8);
s1 = prev->s1;
s2 = prev->s2;
- for (i = 0; i < 16; i++) {
- d = in[i];
- 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 = (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;
+ out += c->channels;
}
prev->s1 = s1;
prev->s2 = s2;
-}
-
-static void adx_decode_stereo(int16_t *out,const uint8_t *in,
- ADXChannelState *prev)
-{
- 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];
- }
-}
-
-/**
- * Decode stream header.
- *
- * @param avctx codec context
- * @param buf packet data
- * @param bufsize packet size
- * @return data offset or negative error code if header is invalid
- */
-static int adx_decode_header(AVCodecContext *avctx, const uint8_t *buf,
- int bufsize)
-{
- int offset;
-
- if (buf[0] != 0x80)
- return AVERROR_INVALIDDATA;
- offset = (AV_RB32(buf) ^ 0x80000000) + 4;
- if (bufsize < offset || memcmp(buf + offset - 6, "(c)CRI", 6))
- return AVERROR_INVALIDDATA;
- avctx->channels = buf[7];
- if (avctx->channels > 2)
- return AVERROR_INVALIDDATA;
- avctx->sample_rate = AV_RB32(buf + 8);
- if (avctx->sample_rate < 1 ||
- avctx->sample_rate > INT_MAX / (avctx->channels * 18 * 8))
- return AVERROR_INVALIDDATA;
- avctx->bit_rate = avctx->sample_rate * avctx->channels * 18 * 8 / 32;
-
- return offset;
+ return 0;
}
-static int adx_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
- AVPacket *avpkt)
+static int adx_decode_frame(AVCodecContext *avctx, void *data,
+ int *got_frame_ptr, AVPacket *avpkt)
{
- const uint8_t *buf0 = avpkt->data;
int buf_size = avpkt->size;
ADXContext *c = avctx->priv_data;
- int16_t *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) {
- av_log(avctx, AV_LOG_ERROR, "invalid stream header\n");
- return hdrsize;
+ int16_t *samples;
+ const uint8_t *buf = avpkt->data;
+ int num_blocks, ch, ret;
+
+ if (c->eof) {
+ *got_frame_ptr = 0;
+ return buf_size;
+ }
+
+ 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;
- buf += hdrsize;
- rest -= hdrsize;
+ 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);
- /* 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 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 (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;
+ /* 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.data[0];
+
+ while (num_blocks--) {
+ for (ch = 0; ch < c->channels; ch++) {
+ if (adx_decode(c, samples + ch, buf, ch)) {
+ c->eof = 1;
+ buf = avpkt->data + avpkt->size;
+ break;
+ }
+ buf_size -= BLOCK_SIZE;
+ buf += BLOCK_SIZE;
}
+ samples += BLOCK_SAMPLES * c->channels;
}
- c->in_temp = rest;
- if (rest) {
- memcpy(c->dec_temp, buf, rest);
- buf += rest;
- }
- *data_size = (uint8_t*)samples - (uint8_t*)data;
- return buf - buf0;
+ *got_frame_ptr = 1;
+ *(AVFrame *)data = c->frame;
+
+ return buf - avpkt->data;
+}
+
+static void adx_decode_flush(AVCodecContext *avctx)
+{
+ ADXContext *c = avctx->priv_data;
+ memset(c->prev, 0, sizeof(c->prev));
+ c->eof = 0;
}
AVCodec ff_adpcm_adx_decoder = {
.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"),
};
projects / ffmpeg / blobdiff