From d14a26edb7c4487df581f11e5c6911dc0e623d08 Mon Sep 17 00:00:00 2001 From: Luca Barbato Date: Sat, 29 Jun 2013 05:29:54 +0200 Subject: wmavoice: conceal clearly corrupted blocks Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind CC: libav-stable@libav.org --- libavcodec/wmavoice.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) (limited to 'libavcodec/wmavoice.c') diff --git a/libavcodec/wmavoice.c b/libavcodec/wmavoice.c index f3d0034ea8..219f4e5529 100644 --- a/libavcodec/wmavoice.c +++ b/libavcodec/wmavoice.c @@ -1052,9 +1052,10 @@ static void aw_parse_coords(WMAVoiceContext *s, GetBitContext *gb, * @param gb bit I/O context * @param block_idx block index in frame [0, 1] * @param fcb structure containing fixed codebook vector info + * @return -1 on error, 0 otherwise */ -static void aw_pulse_set2(WMAVoiceContext *s, GetBitContext *gb, - int block_idx, AMRFixed *fcb) +static int aw_pulse_set2(WMAVoiceContext *s, GetBitContext *gb, + int block_idx, AMRFixed *fcb) { uint16_t use_mask_mem[9]; // only 5 are used, rest is padding uint16_t *use_mask = use_mask_mem + 2; @@ -1116,7 +1117,7 @@ static void aw_pulse_set2(WMAVoiceContext *s, GetBitContext *gb, else if (use_mask[2]) idx = 0x2F; else if (use_mask[3]) idx = 0x3F; else if (use_mask[4]) idx = 0x4F; - else return; + else return -1; idx -= av_log2_16bit(use_mask[idx >> 4]); } if (use_mask[idx >> 4] & (0x8000 >> (idx & 15))) { @@ -1133,6 +1134,7 @@ static void aw_pulse_set2(WMAVoiceContext *s, GetBitContext *gb, /* set offset for next block, relative to start of that block */ n = (MAX_FRAMESIZE / 2 - start_off) % fcb->pitch_lag; s->aw_next_pulse_off_cache = n ? fcb->pitch_lag - n : 0; + return 0; } /** @@ -1295,7 +1297,18 @@ static void synth_block_fcb_acb(WMAVoiceContext *s, GetBitContext *gb, * (fixed) codebook pulses of the speech signal. */ if (frame_desc->fcb_type == FCB_TYPE_AW_PULSES) { aw_pulse_set1(s, gb, block_idx, &fcb); - aw_pulse_set2(s, gb, block_idx, &fcb); + if (aw_pulse_set2(s, gb, block_idx, &fcb)) { + /* Conceal the block with silence and return. + * Skip the correct amount of bits to read the next + * block from the correct offset. */ + int r_idx = pRNG(s->frame_cntr, block_idx, size); + + for (n = 0; n < size; n++) + excitation[n] = + wmavoice_std_codebook[r_idx + n] * s->silence_gain; + skip_bits(gb, 7 + 1); + return; + } } else /* FCB_TYPE_EXC_PULSES */ { int offset_nbits = 5 - frame_desc->log_n_blocks; -- cgit v1.2.3