From b087ce2bee81db8cc5caffb8f0a4f6c7c92a30fe Mon Sep 17 00:00:00 2001 From: Martin Storsjö Date: Fri, 2 Mar 2012 17:03:06 +0200 Subject: g722: Fix the QMF scaling MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This fixes clipping if the encoder input used the full 16 bit input range (samples with a magnitude below 16383 worked fine). The filtered subband samples should be 15 bit maximum, while the code earlier produced them scaled to 16 bit. This makes the decoder output have double the magnitude compared to before. The spec reference samples doesn't test the QMF at all, which was why this part slipped past initially. Signed-off-by: Martin Storsjö --- libavcodec/g722dec.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'libavcodec/g722dec.c') diff --git a/libavcodec/g722dec.c b/libavcodec/g722dec.c index 50a224ba10..72bb0ef3c7 100644 --- a/libavcodec/g722dec.c +++ b/libavcodec/g722dec.c @@ -126,8 +126,8 @@ static int g722_decode_frame(AVCodecContext *avctx, void *data, c->prev_samples[c->prev_samples_pos++] = rlow - rhigh; ff_g722_apply_qmf(c->prev_samples + c->prev_samples_pos - 24, &xout1, &xout2); - *out_buf++ = av_clip_int16(xout1 >> 12); - *out_buf++ = av_clip_int16(xout2 >> 12); + *out_buf++ = av_clip_int16(xout1 >> 11); + *out_buf++ = av_clip_int16(xout2 >> 11); if (c->prev_samples_pos >= PREV_SAMPLES_BUF_SIZE) { memmove(c->prev_samples, c->prev_samples + c->prev_samples_pos - 22, 22 * sizeof(c->prev_samples[0])); -- cgit v1.2.3