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author | Justin Ruggles <justin.ruggles@gmail.com> | 2011-11-20 12:46:41 -0500 |
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committer | Justin Ruggles <justin.ruggles@gmail.com> | 2011-11-26 16:25:06 -0500 |
commit | 837bbd19ebd7a77411462bd505b2f50ce1c9c9bf (patch) | |
tree | 022d838ebcebf18e312ef8977035af073aa78650 /libavcodec/adxdec.c | |
parent | e2d1eace00a80c4b53998397d38ea4e08c5d47f0 (diff) | |
download | ffmpeg-837bbd19ebd7a77411462bd505b2f50ce1c9c9bf.tar.gz |
adx: remove unneeded post-decode channel interleaving
instead interleave channels while decoding
Diffstat (limited to 'libavcodec/adxdec.c')
-rw-r--r-- | libavcodec/adxdec.c | 58 |
1 files changed, 19 insertions, 39 deletions
diff --git a/libavcodec/adxdec.c b/libavcodec/adxdec.c index 887c6d1404..1801c47ac8 100644 --- a/libavcodec/adxdec.c +++ b/libavcodec/adxdec.c @@ -45,8 +45,9 @@ static av_cold int adx_decode_init(AVCodecContext *avctx) * 2nd-order LPC filter applied to it to form the output signal for a single * channel. */ -static void adx_decode(int16_t *out, const uint8_t *in, ADXChannelState *prev) +static void adx_decode(ADXContext *c, int16_t *out, const uint8_t *in, int ch) { + ADXChannelState *prev = &c->prev[ch]; int scale = AV_RB16(in); int i; int s0, s1, s2, d; @@ -60,33 +61,21 @@ static void adx_decode(int16_t *out, const uint8_t *in, ADXChannelState *prev) s0 = (BASEVOL * d * scale + SCALE1 * s1 - SCALE2 * s2) >> 14; s2 = s1; s1 = av_clip_int16(s0); - *out++ = s1; + *out = s1; + out += c->channels; d = in[i]; d = (signed char)(d << 4) >> 4; s0 = (BASEVOL * d * scale + SCALE1 * s1 - SCALE2 * s2) >> 14; s2 = s1; s1 = av_clip_int16(s0); - *out++ = s1; + *out = s1; + out += c->channels; } prev->s1 = s1; prev->s2 = s2; } -static void adx_decode_stereo(int16_t *out,const uint8_t *in, - ADXChannelState *prev) -{ - short tmp[32*2]; - int i; - - adx_decode(tmp, in, prev); - adx_decode(tmp+32, in+18, prev+1); - for (i = 0; i < 32; i++) { - out[i*2 ] = tmp[i ]; - out[i*2+1] = tmp[i+32]; - } -} - /** * Decode stream header. * @@ -98,6 +87,7 @@ static void adx_decode_stereo(int16_t *out,const uint8_t *in, static int adx_decode_header(AVCodecContext *avctx, const uint8_t *buf, int bufsize) { + ADXContext *c = avctx->priv_data; int offset; if (buf[0] != 0x80) @@ -106,7 +96,7 @@ static int adx_decode_header(AVCodecContext *avctx, const uint8_t *buf, if (bufsize < offset || memcmp(buf + offset - 6, "(c)CRI", 6)) return AVERROR_INVALIDDATA; - avctx->channels = buf[7]; + c->channels = avctx->channels = buf[7]; if (avctx->channels > 2) return AVERROR_INVALIDDATA; avctx->sample_rate = AV_RB32(buf + 8); @@ -149,29 +139,19 @@ static int adx_decode_frame(AVCodecContext *avctx, void *data, int *data_size, memcpy(c->dec_temp + c->in_temp, buf, copysize); rest -= copysize; buf += copysize; - if (avctx->channels == 1) { - adx_decode(samples, c->dec_temp, c->prev); - samples += 32; - } else { - adx_decode_stereo(samples, c->dec_temp, c->prev); - samples += 32*2; - } + adx_decode(c, samples, c->dec_temp, 0); + if (avctx->channels == 2) + adx_decode(c, samples + 1, c->dec_temp + 18, 1); + samples += 32 * c->channels; } - if (avctx->channels == 1) { - while (rest >= 18) { - adx_decode(samples, buf, c->prev); - rest -= 18; - buf += 18; - samples += 32; - } - } else { - while (rest >= 18 * 2) { - adx_decode_stereo(samples, buf, c->prev); - rest -= 18 * 2; - buf += 18 * 2; - samples += 32 * 2; - } + while (rest >= 18 * c->channels) { + adx_decode(c, samples, buf, 0); + if (c->channels == 2) + adx_decode(c, samples + 1, buf + 18, 1); + rest -= 18 * c->channels; + buf += 18 * c->channels; + samples += 32 * c->channels; } c->in_temp = rest; |