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Factorize more code.

Originally committed as revision 12874 to svn://svn.ffmpeg.org/ffmpeg/trunk
tags/v0.5
Michael Niedermayer 18 years ago
parent
commit
5eeba07ec9
1 changed files with 12 additions and 20 deletions
  1. +12
    -20
      libavcodec/alac.c

+ 12
- 20
libavcodec/alac.c View File

@@ -146,7 +146,14 @@ static inline int count_leading_zeros(int32_t input)
}


static inline int decode_postfix(GetBitContext *gb, int x, int k, int limit){
static inline int decode_scalar(GetBitContext *gb, int k, int limit, int readsamplesize){
/* read x - number of 1s before 0 represent the rice */
int x = get_unary_0_9(gb);

if (x > 8) { /* RICE THRESHOLD */
/* use alternative encoding */
x = get_bits(gb, readsamplesize);
} else {
if (k >= limit)
k = limit;

@@ -162,6 +169,7 @@ static inline int decode_postfix(GetBitContext *gb, int x, int k, int limit){
} else
skip_bits(gb, k - 1);
}
}
return x;
}

@@ -184,20 +192,12 @@ static void bastardized_rice_decompress(ALACContext *alac,
int32_t x_modified;
int32_t final_val;

/* read x - number of 1s before 0 represent the rice */
x = get_unary_0_9(&alac->gb);

if (x > 8) { /* RICE THRESHOLD */
/* use alternative encoding */
x = get_bits(&alac->gb, readsamplesize);
} else {
/* standard rice encoding */
int k; /* size of extra bits */

/* read k, that is bits as is */
k = 31 - count_leading_zeros((history >> 9) + 3);
x= decode_postfix(&alac->gb, x, k, rice_kmodifier);
}
x= decode_scalar(&alac->gb, k, rice_kmodifier, readsamplesize);

x_modified = sign_modifier + x;
final_val = (x_modified + 1) / 2;
@@ -216,21 +216,13 @@ static void bastardized_rice_decompress(ALACContext *alac,

/* special case: there may be compressed blocks of 0 */
if ((history < 128) && (output_count+1 < output_size)) {
int block_size;
int block_size, k;

sign_modifier = 1;

x = get_unary_0_9(&alac->gb);

if (x > 8) {
block_size = get_bits(&alac->gb, 16);
} else {
int k;

k = count_leading_zeros(history) + ((history + 16) >> 6 /* / 64 */) - 24;

block_size= decode_postfix(&alac->gb, x, k, rice_kmodifier);
}
block_size= decode_scalar(&alac->gb, k, rice_kmodifier, 16);

if (block_size > 0) {
memset(&output_buffer[output_count+1], 0, block_size * 4);


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