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Code Issues Releases Activity

avcodec/apedec: Implement interim mode detection

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Fixes: NoLegacy.ape
Found-by: Matt Ashland <mail@monkeysaudio.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer
2023-08-26 14:27:49 +02:00
parent 7995e175b8
commit 86c092a0ed
1 changed files with 85 additions and 23 deletions
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108
libavcodec/apedec.c
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@@ -171,6 +171,9 @@ typedef struct APEContext {
int32_t *decoded_buffer;
int decoded_size;
int32_t *decoded[MAX_CHANNELS]; ///< decoded data for each channel
int32_t *interim_buffer;
int interim_size;
int32_t *interim[MAX_CHANNELS]; ///< decoded data for each channel
int blocks_per_loop; ///< maximum number of samples to decode for each call
int16_t* filterbuf[APE_FILTER_LEVELS]; ///< filter memory
@@ -187,6 +190,7 @@ typedef struct APEContext {
const uint8_t *ptr; ///< current position in frame data
int error;
int interim_mode;
void (*entropy_decode_mono)(struct APEContext *ctx, int blockstodecode);
void (*entropy_decode_stereo)(struct APEContext *ctx, int blockstodecode);
@@ -223,6 +227,7 @@ static av_cold int ape_decode_close(AVCodecContext *avctx)
av_freep(&s->filterbuf[i]);
av_freep(&s->decoded_buffer);
av_freep(&s->interim_buffer);
av_freep(&s->data);
s->decoded_size = s->data_size = 0;
@@ -248,12 +253,15 @@ static av_cold int ape_decode_init(AVCodecContext *avctx)
switch (s->bps) {
case 8:
avctx->sample_fmt = AV_SAMPLE_FMT_U8P;
s->interim_mode = 0;
break;
case 16:
avctx->sample_fmt = AV_SAMPLE_FMT_S16P;
s->interim_mode = 0;
break;
case 24:
avctx->sample_fmt = AV_SAMPLE_FMT_S32P;
s->interim_mode = -1;
break;
default:
avpriv_request_sample(avctx,
@@ -1181,7 +1189,7 @@ static av_always_inline int predictor_update_filter(APEPredictor64 *p,
const int decoded, const int filter,
const int delayA, const int delayB,
const int adaptA, const int adaptB,
int compression_level)
int interim_mode)
{
int64_t predictionA, predictionB;
int32_t sign;
@@ -1209,7 +1217,7 @@ static av_always_inline int predictor_update_filter(APEPredictor64 *p,
p->buf[delayB - 3] * p->coeffsB[filter][3] +
p->buf[delayB - 4] * p->coeffsB[filter][4];
if (compression_level < COMPRESSION_LEVEL_INSANE) {
if (interim_mode < 1) {
predictionA = (int32_t)predictionA;
predictionB = (int32_t)predictionB;
p->lastA[filter] = decoded + ((int32_t)(predictionA + (predictionB >> 1)) >> 10);
@@ -1234,32 +1242,73 @@ static av_always_inline int predictor_update_filter(APEPredictor64 *p,
static void predictor_decode_stereo_3950(APEContext *ctx, int count)
{
APEPredictor64 *p = &ctx->predictor64;
int32_t *decoded0 = ctx->decoded[0];
int32_t *decoded1 = ctx->decoded[1];
APEPredictor64 *p_default = &ctx->predictor64;
APEPredictor64 p_interim;
int lcount = count;
int num_passes = 1;
ape_apply_filters(ctx, ctx->decoded[0], ctx->decoded[1], count);
if (ctx->interim_mode == -1) {
p_interim = *p_default;
num_passes ++;
memcpy(ctx->interim[0], ctx->decoded[0], sizeof(*ctx->interim[0])*count);
memcpy(ctx->interim[1], ctx->decoded[1], sizeof(*ctx->interim[1])*count);
}
while (count--) {
/* Predictor Y */
*decoded0 = predictor_update_filter(p, *decoded0, 0, YDELAYA, YDELAYB,
YADAPTCOEFFSA, YADAPTCOEFFSB,
ctx->compression_level);
decoded0++;
*decoded1 = predictor_update_filter(p, *decoded1, 1, XDELAYA, XDELAYB,
XADAPTCOEFFSA, XADAPTCOEFFSB,
ctx->compression_level);
decoded1++;
for (int pass = 0; pass < num_passes; pass++) {
int32_t *decoded0, *decoded1;
int interim_mode = ctx->interim_mode > 0 || pass;
APEPredictor64 *p;
/* Combined */
p->buf++;
/* Have we filled the history buffer? */
if (p->buf == p->historybuffer + HISTORY_SIZE) {
memmove(p->historybuffer, p->buf,
PREDICTOR_SIZE * sizeof(*p->historybuffer));
p->buf = p->historybuffer;
if (pass) {
p = &p_interim;
decoded0 = ctx->interim[0];
decoded1 = ctx->interim[1];
} else {
p = p_default;
decoded0 = ctx->decoded[0];
decoded1 = ctx->decoded[1];
}
p->buf = p->historybuffer;
count = lcount;
while (count--) {
/* Predictor Y */
int32_t a0 = predictor_update_filter(p, *decoded0, 0, YDELAYA, YDELAYB,
YADAPTCOEFFSA, YADAPTCOEFFSB,
interim_mode);
int32_t a1 = predictor_update_filter(p, *decoded1, 1, XDELAYA, XDELAYB,
XADAPTCOEFFSA, XADAPTCOEFFSB,
interim_mode);
*decoded0++ = a0;
*decoded1++ = a1;
if (num_passes > 1) {
int32_t left = a1 - (unsigned)(a0 / 2);
int32_t right = left + a0;
if (FFMAX(FFABS(left), FFABS(right)) > (1<<23)) {
ctx->interim_mode = !interim_mode;
av_log(ctx->avctx, AV_LOG_VERBOSE, "Interim mode: %d\n", ctx->interim_mode);
break;
}
}
/* Combined */
p->buf++;
/* Have we filled the history buffer? */
if (p->buf == p->historybuffer + HISTORY_SIZE) {
memmove(p->historybuffer, p->buf,
PREDICTOR_SIZE * sizeof(*p->historybuffer));
p->buf = p->historybuffer;
}
}
}
if (num_passes > 1 && ctx->interim_mode > 0) {
memcpy(ctx->decoded[0], ctx->interim[0], sizeof(*ctx->interim[0])*lcount);
memcpy(ctx->decoded[1], ctx->interim[1], sizeof(*ctx->interim[1])*lcount);
*p_default = p_interim;
p_default->buf = p_default->historybuffer;
}
}
@@ -1590,6 +1639,19 @@ static int ape_decode_frame(AVCodecContext *avctx, AVFrame *frame,
s->decoded[0] = s->decoded_buffer;
s->decoded[1] = s->decoded_buffer + FFALIGN(blockstodecode, 8);
if (s->interim_mode < 0) {
av_fast_malloc(&s->interim_buffer, &s->interim_size, decoded_buffer_size);
if (!s->interim_buffer)
return AVERROR(ENOMEM);
memset(s->interim_buffer, 0, decoded_buffer_size);
s->interim[0] = s->interim_buffer;
s->interim[1] = s->interim_buffer + FFALIGN(blockstodecode, 8);
} else {
av_freep(&s->interim_buffer);
s->interim_size = 0;
memset(s->interim, 0, sizeof(s->interim));
}
s->error=0;
if ((s->channels == 1) || (s->frameflags & APE_FRAMECODE_PSEUDO_STEREO))