From 42c7aeea67883b3869ec684b371d3838be52801f Mon Sep 17 00:00:00 2001 From: Vitor Sessak Date: Sun, 7 Sep 2008 13:42:34 +0000 Subject: Factorize broken clipping in its own function and document it. Originally committed as revision 15247 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavcodec/mace.c | 28 ++++++++++++++++------------ 1 file changed, 16 insertions(+), 12 deletions(-) (limited to 'libavcodec/mace.c') diff --git a/libavcodec/mace.c b/libavcodec/mace.c index be5f094aa7..79e9b30ef1 100644 --- a/libavcodec/mace.c +++ b/libavcodec/mace.c @@ -244,6 +244,20 @@ typedef struct MACEContext { ChannelData chd[2]; } MACEContext; +/** + * MACE version of av_clip_int16(). We have to do this to keep binary + * identical output to the binary decoder. + */ +static inline int16_t mace_broken_clip_int16(int n) +{ + if (n > 32767) + return 32767; + else if (n < -32768) + return -32767; + else + return n; +} + static void chomp3(ChannelData *ctx, int16_t *output, uint8_t val, const uint16_t tab1[], const uint16_t tab2[][8], uint32_t numChannels) @@ -252,12 +266,7 @@ static void chomp3(ChannelData *ctx, int16_t *output, uint8_t val, current = (short) tab2[(ctx->index & 0x7f0) >> 4][val]; - if (current + ctx->lev > 32767) - current = 32767; - else if (current + ctx->lev < -32768) - current = -32767; - else - current += ctx->lev; + current = mace_broken_clip_int16(current + ctx->lev); ctx->lev = current - (current >> 3); //*ctx->outPtr++=current >> 8; @@ -286,12 +295,7 @@ static void chomp6(ChannelData *ctx, int16_t *output, uint8_t val, ctx->factor -= 314; } - if (current + ctx->level > 32767) - current = 32767; - else if (current + ctx->level < -32768) - current = -32767; - else - current += ctx->level; + current = mace_broken_clip_int16(current + ctx->level); ctx->level = ((current*ctx->factor) >> 15); current >>= 1; -- cgit v1.2.3