adx: calculate the number of blocks in a packet

This commit is contained in:
Justin Ruggles 2011-11-20 17:53:43 -05:00
parent 05c1f11b56
commit 7ff55d9bdb

View File

@ -122,6 +122,7 @@ static int adx_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
int16_t *samples = data;
const uint8_t *buf = buf0;
int rest = buf_size;
int num_blocks;
if (!c->header_parsed) {
int hdrsize = adx_decode_header(avctx, buf, rest);
@ -136,8 +137,15 @@ static int adx_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
/* 18 bytes of data are expanded into 32*2 bytes of audio,
so guard against buffer overflows */
if (rest / (BLOCK_SIZE * c->channels) > *data_size / (BLOCK_SAMPLES * c->channels))
num_blocks = (rest + c->in_temp) / (BLOCK_SIZE * c->channels);
if (num_blocks > *data_size / (BLOCK_SAMPLES * c->channels)) {
rest = (*data_size / (BLOCK_SAMPLES * c->channels)) * BLOCK_SIZE;
num_blocks = (rest + c->in_temp) / (BLOCK_SIZE * c->channels);
}
if (!num_blocks) {
av_log(avctx, AV_LOG_ERROR, "packet is too small\n");
return AVERROR_INVALIDDATA;
}
if (c->in_temp) {
int copysize = BLOCK_SIZE * avctx->channels - c->in_temp;
@ -148,9 +156,10 @@ static int adx_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
if (avctx->channels == 2)
adx_decode(c, samples + 1, c->dec_temp + BLOCK_SIZE, 1);
samples += BLOCK_SAMPLES * c->channels;
num_blocks--;
}
while (rest >= BLOCK_SIZE * c->channels) {
while (num_blocks--) {
adx_decode(c, samples, buf, 0);
if (c->channels == 2)
adx_decode(c, samples + 1, buf + BLOCK_SIZE, 1);