diff options
Diffstat (limited to 'libavcodec/mpc7.c')
-rw-r--r-- | libavcodec/mpc7.c | 46 |
1 files changed, 29 insertions, 17 deletions
diff --git a/libavcodec/mpc7.c b/libavcodec/mpc7.c index c60a621c65..5693c4ddb2 100644 --- a/libavcodec/mpc7.c +++ b/libavcodec/mpc7.c @@ -200,34 +200,46 @@ static int mpc7_decode_frame(AVCodecContext * avctx, void *data, int *got_frame_ptr, AVPacket *avpkt) { const uint8_t *buf = avpkt->data; - int buf_size = avpkt->size; + int buf_size; MPCContext *c = avctx->priv_data; GetBitContext gb; int i, ch; int mb = -1; Band *bands = c->bands; - int off, ret; + int off, ret, last_frame, skip; int bits_used, bits_avail; memset(bands, 0, sizeof(*bands) * (c->maxbands + 1)); - if(buf_size <= 4){ - av_log(avctx, AV_LOG_ERROR, "Too small buffer passed (%i bytes)\n", buf_size); - return AVERROR(EINVAL); + + buf_size = avpkt->size & ~3; + if (buf_size <= 0) { + av_log(avctx, AV_LOG_ERROR, "packet size is too small (%i bytes)\n", + avpkt->size); + return AVERROR_INVALIDDATA; + } + if (buf_size != avpkt->size) { + av_log(avctx, AV_LOG_WARNING, "packet size is not a multiple of 4. " + "extra bytes at the end will be skipped.\n"); } + skip = buf[0]; + last_frame = buf[1]; + buf += 4; + buf_size -= 4; + /* get output buffer */ - c->frame.nb_samples = buf[1] ? c->lastframelen : MPC_FRAME_SIZE; + c->frame.nb_samples = last_frame ? c->lastframelen : MPC_FRAME_SIZE; if ((ret = avctx->get_buffer(avctx, &c->frame)) < 0) { av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); return ret; } - av_fast_padded_malloc(&c->buffer, &c->buffer_size, FFALIGN(buf_size - 1, 4)); - if (!c->buffer) + av_fast_padded_malloc(&c->bits, &c->buf_size, buf_size); + if (!c->bits) return AVERROR(ENOMEM); - c->dsp.bswap_buf((uint32_t*)c->buffer, (const uint32_t*)(buf + 4), (buf_size - 4) >> 2); - init_get_bits(&gb, c->buffer, (buf_size - 4)* 8); - skip_bits_long(&gb, buf[0]); + c->dsp.bswap_buf((uint32_t *)c->bits, (const uint32_t *)buf, buf_size >> 2); + init_get_bits(&gb, c->bits, buf_size * 8); + skip_bits_long(&gb, skip); /* read subband indexes */ for(i = 0; i <= c->maxbands; i++){ @@ -284,21 +296,21 @@ static int mpc7_decode_frame(AVCodecContext * avctx, void *data, ff_mpc_dequantize_and_synth(c, mb, c->frame.data[0], 2); bits_used = get_bits_count(&gb); - bits_avail = (buf_size - 4) * 8; - if(!buf[1] && ((bits_avail < bits_used) || (bits_used + 32 <= bits_avail))){ + bits_avail = buf_size * 8; + if (!last_frame && ((bits_avail < bits_used) || (bits_used + 32 <= bits_avail))) { av_log(NULL,0, "Error decoding frame: used %i of %i bits\n", bits_used, bits_avail); return -1; } if(c->frames_to_skip){ c->frames_to_skip--; *got_frame_ptr = 0; - return buf_size; + return avpkt->size; } *got_frame_ptr = 1; *(AVFrame *)data = c->frame; - return buf_size; + return avpkt->size; } static void mpc7_decode_flush(AVCodecContext *avctx) @@ -312,8 +324,8 @@ static void mpc7_decode_flush(AVCodecContext *avctx) static av_cold int mpc7_decode_close(AVCodecContext *avctx) { MPCContext *c = avctx->priv_data; - av_freep(&c->buffer); - c->buffer_size = 0; + av_freep(&c->bits); + c->buf_size = 0; return 0; } |