From fbb6b49dabc3398440c6dfa838aa090a7a6ebc0d Mon Sep 17 00:00:00 2001 From: Justin Ruggles Date: Sun, 13 Feb 2011 14:49:50 -0500 Subject: ac3enc: Add x86-optimized function to speed up log2_tab(). AC3DSPContext.ac3_max_msb_abs_int16() finds the maximum MSB of the absolute value of each element in an array of int16_t. Signed-off-by: Ronald S. Bultje --- libavcodec/ac3dsp.h | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'libavcodec/ac3dsp.h') diff --git a/libavcodec/ac3dsp.h b/libavcodec/ac3dsp.h index 7f13b11f3b..a4f141f2f5 100644 --- a/libavcodec/ac3dsp.h +++ b/libavcodec/ac3dsp.h @@ -35,6 +35,17 @@ typedef struct AC3DSPContext { * @param nb_coefs number of frequency coefficients. */ void (*ac3_exponent_min)(uint8_t *exp, int num_reuse_blocks, int nb_coefs); + + /** + * Calculate the maximum MSB of the absolute value of each element in an + * array of int16_t. + * @param src input array + * constraints: align 16. values must be in range [-32767,32767] + * @param len number of values in the array + * constraints: multiple of 16 greater than 0 + * @return a value with the same MSB as max(abs(src[])) + */ + int (*ac3_max_msb_abs_int16)(const int16_t *src, int len); } AC3DSPContext; void ff_ac3dsp_init (AC3DSPContext *c); -- cgit v1.2.3