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Merge "remove some variable shadowing"

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This commit is contained in:
James Zern
2012-05-17 14:03:10 -07:00
committed by Gerrit Code Review
parent 817c9dce61 37a77a6bf4
commit 778c52284b
6 changed files with 68 additions and 68 deletions
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84
src/utils/huffman_encode.c
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@ -31,9 +31,6 @@ static int ValuesShouldBeCollapsedToStrideAverage(int a, int b) {
// Change the population counts in a way that the consequent
// Hufmann tree compression, especially its RLE-part, give smaller output.
static int OptimizeHuffmanForRle(int length, int* const counts) {
int stride;
int limit;
int sum;
uint8_t* good_for_rle;
// 1) Let's make the Huffman code more compatible with rle encoding.
int i;
@ -77,48 +74,50 @@ static int OptimizeHuffmanForRle(int length, int* const counts) {
}
}
// 3) Let's replace those population counts that lead to more rle codes.
stride = 0;
limit = counts[0];
sum = 0;
for (i = 0; i < length + 1; ++i) {
if (i == length || good_for_rle[i] ||
(i != 0 && good_for_rle[i - 1]) ||
!ValuesShouldBeCollapsedToStrideAverage(counts[i], limit)) {
if (stride >= 4 || (stride >= 3 && sum == 0)) {
int k;
// The stride must end, collapse what we have, if we have enough (4).
int count = (sum + stride / 2) / stride;
if (count < 1) {
count = 1;
{
int stride = 0;
int limit = counts[0];
int sum = 0;
for (i = 0; i < length + 1; ++i) {
if (i == length || good_for_rle[i] ||
(i != 0 && good_for_rle[i - 1]) ||
!ValuesShouldBeCollapsedToStrideAverage(counts[i], limit)) {
if (stride >= 4 || (stride >= 3 && sum == 0)) {
int k;
// The stride must end, collapse what we have, if we have enough (4).
int count = (sum + stride / 2) / stride;
if (count < 1) {
count = 1;
}
if (sum == 0) {
// Don't make an all zeros stride to be upgraded to ones.
count = 0;
}
for (k = 0; k < stride; ++k) {
// We don't want to change value at counts[i],
// that is already belonging to the next stride. Thus - 1.
counts[i - k - 1] = count;
}
}
if (sum == 0) {
// Don't make an all zeros stride to be upgraded to ones.
count = 0;
}
for (k = 0; k < stride; ++k) {
// We don't want to change value at counts[i],
// that is already belonging to the next stride. Thus - 1.
counts[i - k - 1] = count;
stride = 0;
sum = 0;
if (i < length - 3) {
// All interesting strides have a count of at least 4,
// at least when non-zeros.
limit = (counts[i] + counts[i + 1] +
counts[i + 2] + counts[i + 3] + 2) / 4;
} else if (i < length) {
limit = counts[i];
} else {
limit = 0;
}
}
stride = 0;
sum = 0;
if (i < length - 3) {
// All interesting strides have a count of at least 4,
// at least when non-zeros.
limit = (counts[i] + counts[i + 1] +
counts[i + 2] + counts[i + 3] + 2) / 4;
} else if (i < length) {
limit = counts[i];
} else {
limit = 0;
}
}
++stride;
if (i != length) {
sum += counts[i];
if (stride >= 4) {
limit = (sum + stride / 2) / stride;
++stride;
if (i != length) {
sum += counts[i];
if (stride >= 4) {
limit = (sum + stride / 2) / stride;
}
}
}
}
@ -266,7 +265,6 @@ static int GenerateOptimalTree(const int* const histogram, int histogram_size,
{
// Test if this Huffman tree satisfies our 'tree_depth_limit' criteria.
int max_depth = bit_depths[0];
int j;
for (j = 1; j < histogram_size; ++j) {
if (max_depth < bit_depths[j]) {
max_depth = bit_depths[j];