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Merge "update the Unfilter API in dsp to process one row independently"

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This commit is contained in:
Pascal Massimino 2016-04-22 17:33:41 +00:00 committed by Gerrit Code Review
commit de47492e91
8 changed files with 297 additions and 308 deletions
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31
src/dec/alpha.c
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@ -111,17 +111,29 @@ static int ALPHDecode(VP8Decoder* const dec, int row, int num_rows) {
ALPHDecoder* const alph_dec = dec->alph_dec_; ALPHDecoder* const alph_dec = dec->alph_dec_;
const int width = alph_dec->width_; const int width = alph_dec->width_;
const int height = alph_dec->io_.crop_bottom; const int height = alph_dec->io_.crop_bottom;
uint8_t* const output = dec->alpha_plane_;
if (alph_dec->method_ == ALPHA_NO_COMPRESSION) { if (alph_dec->method_ == ALPHA_NO_COMPRESSION) {
const size_t offset = row * width; int y;
const size_t num_pixels = num_rows * width; const uint8_t* prev_line = dec->alpha_prev_line_;
assert(dec->alpha_data_size_ >= ALPHA_HEADER_LEN + offset + num_pixels); const uint8_t* deltas = dec->alpha_data_ + ALPHA_HEADER_LEN + row * width;
memcpy(dec->alpha_plane_ + offset, uint8_t* dst = dec->alpha_plane_ + row * width;
dec->alpha_data_ + ALPHA_HEADER_LEN + offset, num_pixels); assert(deltas <= &dec->alpha_data_[dec->alpha_data_size_]);
if (WebPUnfilters[alph_dec->filter_] != NULL) { if (alph_dec->filter_ != WEBP_FILTER_NONE) {
WebPUnfilters[alph_dec->filter_](width, height, width, assert(WebPUnfilters[alph_dec->filter_] != NULL);
row, num_rows, output); for (y = 0; y < num_rows; ++y) {
WebPUnfilters[alph_dec->filter_](prev_line, deltas, dst, width);
prev_line = dst;
dst += width;
deltas += width;
} }
} else {
for (y = 0; y < num_rows; ++y) {
memcpy(dst, deltas, width * sizeof(*dst));
prev_line = dst;
dst += width;
deltas += width;
}
}
dec->alpha_prev_line_ = prev_line;
} else { // alph_dec->method_ == ALPHA_LOSSLESS_COMPRESSION } else { // alph_dec->method_ == ALPHA_LOSSLESS_COMPRESSION
assert(alph_dec->vp8l_dec_ != NULL); assert(alph_dec->vp8l_dec_ != NULL);
if (!VP8LDecodeAlphaImageStream(alph_dec, row + num_rows)) { if (!VP8LDecodeAlphaImageStream(alph_dec, row + num_rows)) {
@ -146,6 +158,7 @@ static int AllocateAlphaPlane(VP8Decoder* const dec, const VP8Io* const io) {
return 0; return 0;
} }
dec->alpha_plane_ = dec->alpha_plane_mem_; dec->alpha_plane_ = dec->alpha_plane_mem_;
dec->alpha_prev_line_ = NULL;
return 1; return 1;
} }

1
src/dec/alphai.h
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@ -36,6 +36,7 @@ struct ALPHDecoder {
// pixel, sometimes VP8LDecoder may need to allocate // pixel, sometimes VP8LDecoder may need to allocate
// 4 bytes per pixel internally during decode. // 4 bytes per pixel internally during decode.
uint8_t* output_; uint8_t* output_;
const uint8_t* prev_line_; // last output row (or NULL)
}; };
//------------------------------------------------------------------------------ //------------------------------------------------------------------------------

1
src/dec/vp8i.h
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@ -261,6 +261,7 @@ struct VP8Decoder {
int is_alpha_decoded_; // true if alpha_data_ is decoded in alpha_plane_ int is_alpha_decoded_; // true if alpha_data_ is decoded in alpha_plane_
uint8_t* alpha_plane_mem_; // memory allocated for alpha_plane_ uint8_t* alpha_plane_mem_; // memory allocated for alpha_plane_
uint8_t* alpha_plane_; // output. Persistent, contains the whole data. uint8_t* alpha_plane_; // output. Persistent, contains the whole data.
const uint8_t* alpha_prev_line_; // last decoded alpha row (or NULL)
int alpha_dithering_; // derived from decoding options (0=off, 100=full) int alpha_dithering_; // derived from decoding options (0=off, 100=full)
}; };

55
src/dec/vp8l.c
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@ -771,35 +771,46 @@ static int Is8bOptimizable(const VP8LMetadata* const hdr) {
return 1; return 1;
} }
static void ExtractPalettedAlphaRows(VP8LDecoder* const dec, int row) { static void AlphaApplyFilter(ALPHDecoder* const alph_dec,
int first_row, int last_row,
uint8_t* out, int stride) {
if (alph_dec->filter_ != WEBP_FILTER_NONE) {
int y;
const uint8_t* prev_line = alph_dec->prev_line_;
assert(WebPUnfilters[alph_dec->filter_] != NULL);
for (y = first_row; y < last_row; ++y) {
WebPUnfilters[alph_dec->filter_](prev_line, out, out, stride);
prev_line = out;
out += stride;
}
alph_dec->prev_line_ = prev_line;
}
}
static void ExtractPalettedAlphaRows(VP8LDecoder* const dec, int last_row) {
// For vertical and gradient filtering, we need to decode the part above the // For vertical and gradient filtering, we need to decode the part above the
// crop_top row, in order to have the correct spatial predictors. // crop_top row, in order to have the correct spatial predictors.
const ALPHDecoder* const alph_dec = (const ALPHDecoder*)dec->io_->opaque; ALPHDecoder* const alph_dec = (ALPHDecoder*)dec->io_->opaque;
const int top_row = const int top_row =
(alph_dec->filter_ == WEBP_FILTER_NONE || (alph_dec->filter_ == WEBP_FILTER_NONE ||
alph_dec->filter_ == WEBP_FILTER_HORIZONTAL) ? dec->io_->crop_top alph_dec->filter_ == WEBP_FILTER_HORIZONTAL) ? dec->io_->crop_top
: dec->last_row_; : dec->last_row_;
const int first_row = (dec->last_row_ < top_row) ? top_row : dec->last_row_; const int first_row = (dec->last_row_ < top_row) ? top_row : dec->last_row_;
assert(row <= dec->io_->crop_bottom); assert(last_row <= dec->io_->crop_bottom);
if (row > first_row) { if (last_row > first_row) {
// Special method for paletted alpha data. We only process the cropped area. // Special method for paletted alpha data. We only process the cropped area.
const int width = dec->io_->width; const int width = dec->io_->width;
uint8_t* const out = alph_dec->output_ + width * first_row; uint8_t* out = alph_dec->output_ + width * first_row;
const uint8_t* const in = const uint8_t* const in =
(uint8_t*)dec->pixels_ + dec->width_ * first_row; (uint8_t*)dec->pixels_ + dec->width_ * first_row;
VP8LTransform* const transform = &dec->transforms_[0]; VP8LTransform* const transform = &dec->transforms_[0];
assert(dec->next_transform_ == 1); assert(dec->next_transform_ == 1);
assert(transform->type_ == COLOR_INDEXING_TRANSFORM); assert(transform->type_ == COLOR_INDEXING_TRANSFORM);
VP8LColorIndexInverseTransformAlpha(transform, first_row, row, VP8LColorIndexInverseTransformAlpha(transform, first_row, last_row,
in, out); in, out);
if (alph_dec->filter_ != WEBP_FILTER_NONE) { AlphaApplyFilter(alph_dec, first_row, last_row, out, width);
assert(WebPUnfilters[alph_dec->filter_] != NULL);
WebPUnfilters[alph_dec->filter_](width, dec->io_->height, width,
first_row, row - first_row,
alph_dec->output_);
} }
} dec->last_row_ = dec->last_out_row_ = last_row;
dec->last_row_ = dec->last_out_row_ = row;
} }
//------------------------------------------------------------------------------ //------------------------------------------------------------------------------
@ -1452,29 +1463,25 @@ static int AllocateInternalBuffers8b(VP8LDecoder* const dec) {
//------------------------------------------------------------------------------ //------------------------------------------------------------------------------
// Special row-processing that only stores the alpha data. // Special row-processing that only stores the alpha data.
static void ExtractAlphaRows(VP8LDecoder* const dec, int row) { static void ExtractAlphaRows(VP8LDecoder* const dec, int last_row) {
const int num_rows = row - dec->last_row_; const int num_rows = last_row - dec->last_row_;
const uint32_t* const in = dec->pixels_ + dec->width_ * dec->last_row_; const uint32_t* const in = dec->pixels_ + dec->width_ * dec->last_row_;
assert(row <= dec->io_->crop_bottom); assert(last_row <= dec->io_->crop_bottom);
if (num_rows > 0) { if (num_rows > 0) {
// Extract alpha (which is stored in the green plane). // Extract alpha (which is stored in the green plane).
const ALPHDecoder* const alph_dec = (const ALPHDecoder*)dec->io_->opaque; ALPHDecoder* const alph_dec = (ALPHDecoder*)dec->io_->opaque;
uint8_t* const output = alph_dec->output_; uint8_t* const output = alph_dec->output_;
const int width = dec->io_->width; // the final width (!= dec->width_) const int width = dec->io_->width; // the final width (!= dec->width_)
const int cache_pixs = width * num_rows; const int cache_pixs = width * num_rows;
uint8_t* const dst = output + width * dec->last_row_; uint8_t* dst = output + width * dec->last_row_;
const uint32_t* const src = dec->argb_cache_; const uint32_t* const src = dec->argb_cache_;
int i; int i;
ApplyInverseTransforms(dec, num_rows, in); ApplyInverseTransforms(dec, num_rows, in);
for (i = 0; i < cache_pixs; ++i) dst[i] = (src[i] >> 8) & 0xff; for (i = 0; i < cache_pixs; ++i) dst[i] = (src[i] >> 8) & 0xff;
if (alph_dec->filter_ != WEBP_FILTER_NONE) { AlphaApplyFilter(alph_dec, dec->last_row_, last_row, dst, width);
assert(WebPUnfilters[alph_dec->filter_] != NULL);
WebPUnfilters[alph_dec->filter_](width, dec->io_->height, width,
dec->last_row_, num_rows, output);
} }
} dec->last_row_ = dec->last_out_row_ = last_row;
dec->last_row_ = dec->last_out_row_ = row;
} }
int VP8LDecodeAlphaHeader(ALPHDecoder* const alph_dec, int VP8LDecodeAlphaHeader(ALPHDecoder* const alph_dec,

6
src/dsp/dsp.h
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@ -503,8 +503,10 @@ typedef enum { // Filter types.
typedef void (*WebPFilterFunc)(const uint8_t* in, int width, int height, typedef void (*WebPFilterFunc)(const uint8_t* in, int width, int height,
int stride, uint8_t* out); int stride, uint8_t* out);
typedef void (*WebPUnfilterFunc)(int width, int height, int stride, // In-place un-filtering.
int row, int num_rows, uint8_t* data); // Warning! 'prev_line' pointer can be equal to 'cur_line' or 'preds'.
typedef void (*WebPUnfilterFunc)(const uint8_t* prev_line, const uint8_t* preds,
uint8_t* cur_line, int width);
// Filter the given data using the given predictor. // Filter the given data using the given predictor.
// 'in' corresponds to a 2-dimensional pixel array of size (stride * height) // 'in' corresponds to a 2-dimensional pixel array of size (stride * height)

39
src/dsp/filters.c
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@ -184,19 +184,40 @@ static void GradientFilter(const uint8_t* data, int width, int height,
//------------------------------------------------------------------------------ //------------------------------------------------------------------------------
static void VerticalUnfilter(int width, int height, int stride, int row, static void HorizontalUnfilter(const uint8_t* prev, const uint8_t* in,
int num_rows, uint8_t* data) { uint8_t* out, int width) {
DoVerticalFilter(data, width, height, stride, row, num_rows, 1, data); uint8_t pred = (prev == NULL) ? 0 : prev[0];
int i;
for (i = 0; i < width; ++i) {
out[i] = pred + in[i];
pred = out[i];
}
} }
static void HorizontalUnfilter(int width, int height, int stride, int row, static void VerticalUnfilter(const uint8_t* prev, const uint8_t* in,
int num_rows, uint8_t* data) { uint8_t* out, int width) {
DoHorizontalFilter(data, width, height, stride, row, num_rows, 1, data); if (prev == NULL) {
HorizontalUnfilter(NULL, in, out, width);
} else {
int i;
for (i = 0; i < width; ++i) out[i] = prev[i] + in[i];
}
} }
static void GradientUnfilter(int width, int height, int stride, int row, static void GradientUnfilter(const uint8_t* prev, const uint8_t* in,
int num_rows, uint8_t* data) { uint8_t* out, int width) {
DoGradientFilter(data, width, height, stride, row, num_rows, 1, data); if (prev == NULL) {
HorizontalUnfilter(NULL, in, out, width);
} else {
uint8_t top = prev[0], top_left = top, left = top;
int i;
for (i = 0; i < width; ++i) {
top = prev[i]; // need to read this first, in case prev==out
left = in[i] + GradientPredictor(left, top, top_left);
top_left = top;
out[i] = left;
}
}
} }
//------------------------------------------------------------------------------ //------------------------------------------------------------------------------

162
src/dsp/filters_mips_dsp_r2.c
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@ -33,12 +33,9 @@
assert(row >= 0 && num_rows > 0 && row + num_rows <= height); \ assert(row >= 0 && num_rows > 0 && row + num_rows <= height); \
(void)height; // Silence unused warning. (void)height; // Silence unused warning.
// if INVERSE
// preds == &dst[-1] == &src[-1]
// else
// preds == &src[-1] != &dst[-1] // preds == &src[-1] != &dst[-1]
#define DO_PREDICT_LINE(SRC, DST, LENGTH, INVERSE) do { \ #define DO_PREDICT_LINE(SRC, DST, LENGTH) do { \
const uint8_t* psrc = (uint8_t*)(SRC); \ const uint8_t* psrc = (const uint8_t*)(SRC); \
uint8_t* pdst = (uint8_t*)(DST); \ uint8_t* pdst = (uint8_t*)(DST); \
const int ilength = (int)(LENGTH); \ const int ilength = (int)(LENGTH); \
int temp0, temp1, temp2, temp3, temp4, temp5, temp6; \ int temp0, temp1, temp2, temp3, temp4, temp5, temp6; \
@ -48,25 +45,6 @@
"srl %[temp0], %[length], 0x2 \n\t" \ "srl %[temp0], %[length], 0x2 \n\t" \
"beqz %[temp0], 4f \n\t" \ "beqz %[temp0], 4f \n\t" \
" andi %[temp6], %[length], 0x3 \n\t" \ " andi %[temp6], %[length], 0x3 \n\t" \
".if " #INVERSE " \n\t" \
"lbu %[temp1], -1(%[src]) \n\t" \
"1: \n\t" \
"lbu %[temp2], 0(%[src]) \n\t" \
"lbu %[temp3], 1(%[src]) \n\t" \
"lbu %[temp4], 2(%[src]) \n\t" \
"lbu %[temp5], 3(%[src]) \n\t" \
"addiu %[src], %[src], 4 \n\t" \
"addiu %[temp0], %[temp0], -1 \n\t" \
"addu %[temp2], %[temp2], %[temp1] \n\t" \
"addu %[temp3], %[temp3], %[temp2] \n\t" \
"addu %[temp4], %[temp4], %[temp3] \n\t" \
"addu %[temp1], %[temp5], %[temp4] \n\t" \
"sb %[temp2], -4(%[src]) \n\t" \
"sb %[temp3], -3(%[src]) \n\t" \
"sb %[temp4], -2(%[src]) \n\t" \
"bnez %[temp0], 1b \n\t" \
" sb %[temp1], -1(%[src]) \n\t" \
".else \n\t" \
"1: \n\t" \ "1: \n\t" \
"ulw %[temp1], -1(%[src]) \n\t" \ "ulw %[temp1], -1(%[src]) \n\t" \
"ulw %[temp2], 0(%[src]) \n\t" \ "ulw %[temp2], 0(%[src]) \n\t" \
@ -76,7 +54,6 @@
"usw %[temp3], 0(%[dst]) \n\t" \ "usw %[temp3], 0(%[dst]) \n\t" \
"bnez %[temp0], 1b \n\t" \ "bnez %[temp0], 1b \n\t" \
" addiu %[dst], %[dst], 4 \n\t" \ " addiu %[dst], %[dst], 4 \n\t" \
".endif \n\t" \
"4: \n\t" \ "4: \n\t" \
"beqz %[temp6], 3f \n\t" \ "beqz %[temp6], 3f \n\t" \
" nop \n\t" \ " nop \n\t" \
@ -84,13 +61,8 @@
"lbu %[temp1], -1(%[src]) \n\t" \ "lbu %[temp1], -1(%[src]) \n\t" \
"lbu %[temp2], 0(%[src]) \n\t" \ "lbu %[temp2], 0(%[src]) \n\t" \
"addiu %[src], %[src], 1 \n\t" \ "addiu %[src], %[src], 1 \n\t" \
".if " #INVERSE " \n\t" \
"addu %[temp3], %[temp1], %[temp2] \n\t" \
"sb %[temp3], -1(%[src]) \n\t" \
".else \n\t" \
"subu %[temp3], %[temp1], %[temp2] \n\t" \ "subu %[temp3], %[temp1], %[temp2] \n\t" \
"sb %[temp3], 0(%[dst]) \n\t" \ "sb %[temp3], 0(%[dst]) \n\t" \
".endif \n\t" \
"addiu %[temp6], %[temp6], -1 \n\t" \ "addiu %[temp6], %[temp6], -1 \n\t" \
"bnez %[temp6], 2b \n\t" \ "bnez %[temp6], 2b \n\t" \
" addiu %[dst], %[dst], 1 \n\t" \ " addiu %[dst], %[dst], 1 \n\t" \
@ -105,12 +77,8 @@
} while (0) } while (0)
static WEBP_INLINE void PredictLine(const uint8_t* src, uint8_t* dst, static WEBP_INLINE void PredictLine(const uint8_t* src, uint8_t* dst,
int length, int inverse) { int length) {
if (inverse) { DO_PREDICT_LINE(src, dst, length);
DO_PREDICT_LINE(src, dst, length, 1);
} else {
DO_PREDICT_LINE(src, dst, length, 0);
}
} }
#define DO_PREDICT_LINE_VERTICAL(SRC, PRED, DST, LENGTH, INVERSE) do { \ #define DO_PREDICT_LINE_VERTICAL(SRC, PRED, DST, LENGTH, INVERSE) do { \
@ -172,16 +140,12 @@ static WEBP_INLINE void PredictLine(const uint8_t* src, uint8_t* dst,
); \ ); \
} while (0) } while (0)
#define PREDICT_LINE_ONE_PASS(SRC, PRED, DST, INVERSE) do { \ #define PREDICT_LINE_ONE_PASS(SRC, PRED, DST) do { \
int temp1, temp2, temp3; \ int temp1, temp2, temp3; \
__asm__ volatile ( \ __asm__ volatile ( \
"lbu %[temp1], 0(%[src]) \n\t" \ "lbu %[temp1], 0(%[src]) \n\t" \
"lbu %[temp2], 0(%[pred]) \n\t" \ "lbu %[temp2], 0(%[pred]) \n\t" \
".if " #INVERSE " \n\t" \
"addu %[temp3], %[temp1], %[temp2] \n\t" \
".else \n\t" \
"subu %[temp3], %[temp1], %[temp2] \n\t" \ "subu %[temp3], %[temp1], %[temp2] \n\t" \
".endif \n\t" \
"sb %[temp3], 0(%[dst]) \n\t" \ "sb %[temp3], 0(%[dst]) \n\t" \
: [temp1]"=&r"(temp1), [temp2]"=&r"(temp2), [temp3]"=&r"(temp3) \ : [temp1]"=&r"(temp1), [temp2]"=&r"(temp2), [temp3]"=&r"(temp3) \
: [pred]"r"((PRED)), [dst]"r"((DST)), [src]"r"((SRC)) \ : [pred]"r"((PRED)), [dst]"r"((DST)), [src]"r"((SRC)) \
@ -192,10 +156,10 @@ static WEBP_INLINE void PredictLine(const uint8_t* src, uint8_t* dst,
//------------------------------------------------------------------------------ //------------------------------------------------------------------------------
// Horizontal filter. // Horizontal filter.
#define FILTER_LINE_BY_LINE(INVERSE) do { \ #define FILTER_LINE_BY_LINE do { \
while (row < last_row) { \ while (row < last_row) { \
PREDICT_LINE_ONE_PASS(in, preds - stride, out, INVERSE); \ PREDICT_LINE_ONE_PASS(in, preds - stride, out); \
DO_PREDICT_LINE(in + 1, out + 1, width - 1, INVERSE); \ DO_PREDICT_LINE(in + 1, out + 1, width - 1); \
++row; \ ++row; \
preds += stride; \ preds += stride; \
in += stride; \ in += stride; \
@ -206,19 +170,19 @@ static WEBP_INLINE void PredictLine(const uint8_t* src, uint8_t* dst,
static WEBP_INLINE void DoHorizontalFilter(const uint8_t* in, static WEBP_INLINE void DoHorizontalFilter(const uint8_t* in,
int width, int height, int stride, int width, int height, int stride,
int row, int num_rows, int row, int num_rows,
int inverse, uint8_t* out) { uint8_t* out) {
const uint8_t* preds; const uint8_t* preds;
const size_t start_offset = row * stride; const size_t start_offset = row * stride;
const int last_row = row + num_rows; const int last_row = row + num_rows;
SANITY_CHECK(in, out); SANITY_CHECK(in, out);
in += start_offset; in += start_offset;
out += start_offset; out += start_offset;
preds = inverse ? out : in; preds = in;
if (row == 0) { if (row == 0) {
// Leftmost pixel is the same as input for topmost scanline. // Leftmost pixel is the same as input for topmost scanline.
out[0] = in[0]; out[0] = in[0];
PredictLine(in + 1, out + 1, width - 1, inverse); PredictLine(in + 1, out + 1, width - 1);
row = 1; row = 1;
preds += stride; preds += stride;
in += stride; in += stride;
@ -226,31 +190,21 @@ static WEBP_INLINE void DoHorizontalFilter(const uint8_t* in,
} }
// Filter line-by-line. // Filter line-by-line.
if (inverse) { FILTER_LINE_BY_LINE;
FILTER_LINE_BY_LINE(1);
} else {
FILTER_LINE_BY_LINE(0);
} }
}
#undef FILTER_LINE_BY_LINE #undef FILTER_LINE_BY_LINE
static void HorizontalFilter(const uint8_t* data, int width, int height, static void HorizontalFilter(const uint8_t* data, int width, int height,
int stride, uint8_t* filtered_data) { int stride, uint8_t* filtered_data) {
DoHorizontalFilter(data, width, height, stride, 0, height, 0, filtered_data); DoHorizontalFilter(data, width, height, stride, 0, height, filtered_data);
}
static void HorizontalUnfilter(int width, int height, int stride, int row,
int num_rows, uint8_t* data) {
DoHorizontalFilter(data, width, height, stride, row, num_rows, 1, data);
} }
//------------------------------------------------------------------------------ //------------------------------------------------------------------------------
// Vertical filter. // Vertical filter.
#define FILTER_LINE_BY_LINE(INVERSE) do { \ #define FILTER_LINE_BY_LINE do { \
while (row < last_row) { \ while (row < last_row) { \
DO_PREDICT_LINE_VERTICAL(in, preds, out, width, INVERSE); \ DO_PREDICT_LINE_VERTICAL(in, preds, out, width, 0); \
++row; \ ++row; \
preds += stride; \ preds += stride; \
in += stride; \ in += stride; \
@ -260,21 +214,20 @@ static void HorizontalUnfilter(int width, int height, int stride, int row,
static WEBP_INLINE void DoVerticalFilter(const uint8_t* in, static WEBP_INLINE void DoVerticalFilter(const uint8_t* in,
int width, int height, int stride, int width, int height, int stride,
int row, int num_rows, int row, int num_rows, uint8_t* out) {
int inverse, uint8_t* out) {
const uint8_t* preds; const uint8_t* preds;
const size_t start_offset = row * stride; const size_t start_offset = row * stride;
const int last_row = row + num_rows; const int last_row = row + num_rows;
SANITY_CHECK(in, out); SANITY_CHECK(in, out);
in += start_offset; in += start_offset;
out += start_offset; out += start_offset;
preds = inverse ? out : in; preds = in;
if (row == 0) { if (row == 0) {
// Very first top-left pixel is copied. // Very first top-left pixel is copied.
out[0] = in[0]; out[0] = in[0];
// Rest of top scan-line is left-predicted. // Rest of top scan-line is left-predicted.
PredictLine(in + 1, out + 1, width - 1, inverse); PredictLine(in + 1, out + 1, width - 1);
row = 1; row = 1;
in += stride; in += stride;
out += stride; out += stride;
@ -284,24 +237,13 @@ static WEBP_INLINE void DoVerticalFilter(const uint8_t* in,
} }
// Filter line-by-line. // Filter line-by-line.
if (inverse) { FILTER_LINE_BY_LINE;
FILTER_LINE_BY_LINE(1);
} else {
FILTER_LINE_BY_LINE(0);
} }
}
#undef FILTER_LINE_BY_LINE #undef FILTER_LINE_BY_LINE
#undef DO_PREDICT_LINE_VERTICAL
static void VerticalFilter(const uint8_t* data, int width, int height, static void VerticalFilter(const uint8_t* data, int width, int height,
int stride, uint8_t* filtered_data) { int stride, uint8_t* filtered_data) {
DoVerticalFilter(data, width, height, stride, 0, height, 0, filtered_data); DoVerticalFilter(data, width, height, stride, 0, height, filtered_data);
}
static void VerticalUnfilter(int width, int height, int stride, int row,
int num_rows, uint8_t* data) {
DoVerticalFilter(data, width, height, stride, row, num_rows, 1, data);
} }
//------------------------------------------------------------------------------ //------------------------------------------------------------------------------
@ -321,10 +263,10 @@ static WEBP_INLINE int GradientPredictor(uint8_t a, uint8_t b, uint8_t c) {
return temp0; return temp0;
} }
#define FILTER_LINE_BY_LINE(INVERSE, PREDS, OPERATION) do { \ #define FILTER_LINE_BY_LINE(PREDS, OPERATION) do { \
while (row < last_row) { \ while (row < last_row) { \
int w; \ int w; \
PREDICT_LINE_ONE_PASS(in, PREDS - stride, out, INVERSE); \ PREDICT_LINE_ONE_PASS(in, PREDS - stride, out); \
for (w = 1; w < width; ++w) { \ for (w = 1; w < width; ++w) { \
const int pred = GradientPredictor(PREDS[w - 1], \ const int pred = GradientPredictor(PREDS[w - 1], \
PREDS[w - stride], \ PREDS[w - stride], \
@ -339,20 +281,19 @@ static WEBP_INLINE int GradientPredictor(uint8_t a, uint8_t b, uint8_t c) {
static WEBP_INLINE void DoGradientFilter(const uint8_t* in, static WEBP_INLINE void DoGradientFilter(const uint8_t* in,
int width, int height, int stride, int width, int height, int stride,
int row, int num_rows, int row, int num_rows, uint8_t* out) {
int inverse, uint8_t* out) {
const uint8_t* preds; const uint8_t* preds;
const size_t start_offset = row * stride; const size_t start_offset = row * stride;
const int last_row = row + num_rows; const int last_row = row + num_rows;
SANITY_CHECK(in, out); SANITY_CHECK(in, out);
in += start_offset; in += start_offset;
out += start_offset; out += start_offset;
preds = inverse ? out : in; preds = in;
// left prediction for top scan-line // left prediction for top scan-line
if (row == 0) { if (row == 0) {
out[0] = in[0]; out[0] = in[0];
PredictLine(in + 1, out + 1, width - 1, inverse); PredictLine(in + 1, out + 1, width - 1);
row = 1; row = 1;
preds += stride; preds += stride;
in += stride; in += stride;
@ -360,25 +301,50 @@ static WEBP_INLINE void DoGradientFilter(const uint8_t* in,
} }
// Filter line-by-line. // Filter line-by-line.
if (inverse) { FILTER_LINE_BY_LINE(in, -);
FILTER_LINE_BY_LINE(1, out, +);
} else {
FILTER_LINE_BY_LINE(0, in, -);
} }
}
#undef FILTER_LINE_BY_LINE #undef FILTER_LINE_BY_LINE
static void GradientFilter(const uint8_t* data, int width, int height, static void GradientFilter(const uint8_t* data, int width, int height,
int stride, uint8_t* filtered_data) { int stride, uint8_t* filtered_data) {
DoGradientFilter(data, width, height, stride, 0, height, 0, filtered_data); DoGradientFilter(data, width, height, stride, 0, height, filtered_data);
} }
static void GradientUnfilter(int width, int height, int stride, int row, //------------------------------------------------------------------------------
int num_rows, uint8_t* data) {
DoGradientFilter(data, width, height, stride, row, num_rows, 1, data); static void HorizontalUnfilter(const uint8_t* prev, const uint8_t* in,
uint8_t* out, int width) {
int i;
out[0] = in[0] + (prev == NULL ? 0 : prev[0]);
for (i = 1; i < width; ++i) out[i] = in[i] + out[i - 1];
} }
static void VerticalUnfilter(const uint8_t* prev, const uint8_t* in,
uint8_t* out, int width) {
if (prev == NULL) {
HorizontalUnfilter(NULL, in, out, width);
} else {
DO_PREDICT_LINE_VERTICAL(in, prev, out, width, 1);
}
}
static void GradientUnfilter(const uint8_t* prev, const uint8_t* in,
uint8_t* out, int width) {
if (prev == NULL) {
HorizontalUnfilter(NULL, in, out, width);
} else {
uint8_t top = prev[0], top_left = top, left = top;
int i;
for (i = 0; i < width; ++i) {
top = prev[i]; // need to read this first, in case prev==dst
left = in[i] + GradientPredictor(left, top, top_left);
top_left = top;
out[i] = left;
}
}
}
#undef DO_PREDICT_LINE_VERTICAL
#undef PREDICT_LINE_ONE_PASS #undef PREDICT_LINE_ONE_PASS
#undef DO_PREDICT_LINE #undef DO_PREDICT_LINE
#undef SANITY_CHECK #undef SANITY_CHECK
@ -389,13 +355,13 @@ static void GradientUnfilter(int width, int height, int stride, int row,
extern void VP8FiltersInitMIPSdspR2(void); extern void VP8FiltersInitMIPSdspR2(void);
WEBP_TSAN_IGNORE_FUNCTION void VP8FiltersInitMIPSdspR2(void) { WEBP_TSAN_IGNORE_FUNCTION void VP8FiltersInitMIPSdspR2(void) {
WebPFilters[WEBP_FILTER_HORIZONTAL] = HorizontalFilter;
WebPFilters[WEBP_FILTER_VERTICAL] = VerticalFilter;
WebPFilters[WEBP_FILTER_GRADIENT] = GradientFilter;
WebPUnfilters[WEBP_FILTER_HORIZONTAL] = HorizontalUnfilter; WebPUnfilters[WEBP_FILTER_HORIZONTAL] = HorizontalUnfilter;
WebPUnfilters[WEBP_FILTER_VERTICAL] = VerticalUnfilter; WebPUnfilters[WEBP_FILTER_VERTICAL] = VerticalUnfilter;
WebPUnfilters[WEBP_FILTER_GRADIENT] = GradientUnfilter; WebPUnfilters[WEBP_FILTER_GRADIENT] = GradientUnfilter;
WebPFilters[WEBP_FILTER_HORIZONTAL] = HorizontalFilter;
WebPFilters[WEBP_FILTER_VERTICAL] = VerticalFilter;
WebPFilters[WEBP_FILTER_GRADIENT] = GradientFilter;
} }
#else // !WEBP_USE_MIPS_DSP_R2 #else // !WEBP_USE_MIPS_DSP_R2

262
src/dsp/filters_sse2.c
View File

@ -33,23 +33,10 @@
(void)height; // Silence unused warning. (void)height; // Silence unused warning.
static void PredictLineTop(const uint8_t* src, const uint8_t* pred, static void PredictLineTop(const uint8_t* src, const uint8_t* pred,
uint8_t* dst, int length, int inverse) { uint8_t* dst, int length) {
int i; int i;
const int max_pos = length & ~31; const int max_pos = length & ~31;
assert(length >= 0); assert(length >= 0);
if (inverse) {
for (i = 0; i < max_pos; i += 32) {
const __m128i A0 = _mm_loadu_si128((const __m128i*)&src[i + 0]);
const __m128i A1 = _mm_loadu_si128((const __m128i*)&src[i + 16]);
const __m128i B0 = _mm_loadu_si128((const __m128i*)&pred[i + 0]);
const __m128i B1 = _mm_loadu_si128((const __m128i*)&pred[i + 16]);
const __m128i C0 = _mm_add_epi8(A0, B0);
const __m128i C1 = _mm_add_epi8(A1, B1);
_mm_storeu_si128((__m128i*)&dst[i + 0], C0);
_mm_storeu_si128((__m128i*)&dst[i + 16], C1);
}
for (; i < length; ++i) dst[i] = src[i] + pred[i];
} else {
for (i = 0; i < max_pos; i += 32) { for (i = 0; i < max_pos; i += 32) {
const __m128i A0 = _mm_loadu_si128((const __m128i*)&src[i + 0]); const __m128i A0 = _mm_loadu_si128((const __m128i*)&src[i + 0]);
const __m128i A1 = _mm_loadu_si128((const __m128i*)&src[i + 16]); const __m128i A1 = _mm_loadu_si128((const __m128i*)&src[i + 16]);
@ -62,31 +49,12 @@ static void PredictLineTop(const uint8_t* src, const uint8_t* pred,
} }
for (; i < length; ++i) dst[i] = src[i] - pred[i]; for (; i < length; ++i) dst[i] = src[i] - pred[i];
} }
}
// Special case for left-based prediction (when preds==dst-1 or preds==src-1). // Special case for left-based prediction (when preds==dst-1 or preds==src-1).
static void PredictLineLeft(const uint8_t* src, uint8_t* dst, int length, static void PredictLineLeft(const uint8_t* src, uint8_t* dst, int length) {
int inverse) {
int i; int i;
if (length <= 0) return;
if (inverse) {
const int max_pos = length & ~7;
__m128i last = _mm_set_epi32(0, 0, 0, dst[-1]);
for (i = 0; i < max_pos; i += 8) {
const __m128i A0 = _mm_loadl_epi64((const __m128i*)(src + i));
const __m128i A1 = _mm_add_epi8(A0, last);
const __m128i A2 = _mm_slli_si128(A1, 1);
const __m128i A3 = _mm_add_epi8(A1, A2);
const __m128i A4 = _mm_slli_si128(A3, 2);
const __m128i A5 = _mm_add_epi8(A3, A4);
const __m128i A6 = _mm_slli_si128(A5, 4);
const __m128i A7 = _mm_add_epi8(A5, A6);
_mm_storel_epi64((__m128i*)(dst + i), A7);
last = _mm_srli_epi64(A7, 56);
}
for (; i < length; ++i) dst[i] = src[i] + dst[i - 1];
} else {
const int max_pos = length & ~31; const int max_pos = length & ~31;
assert(length >= 0);
for (i = 0; i < max_pos; i += 32) { for (i = 0; i < max_pos; i += 32) {
const __m128i A0 = _mm_loadu_si128((const __m128i*)(src + i + 0 )); const __m128i A0 = _mm_loadu_si128((const __m128i*)(src + i + 0 ));
const __m128i B0 = _mm_loadu_si128((const __m128i*)(src + i + 0 - 1)); const __m128i B0 = _mm_loadu_si128((const __m128i*)(src + i + 0 - 1));
@ -99,17 +67,6 @@ static void PredictLineLeft(const uint8_t* src, uint8_t* dst, int length,
} }
for (; i < length; ++i) dst[i] = src[i] - src[i - 1]; for (; i < length; ++i) dst[i] = src[i] - src[i - 1];
} }
}
static void PredictLineC(const uint8_t* src, const uint8_t* pred,
uint8_t* dst, int length, int inverse) {
int i;
if (inverse) {
for (i = 0; i < length; ++i) dst[i] = src[i] + pred[i];
} else {
for (i = 0; i < length; ++i) dst[i] = src[i] - pred[i];
}
}
//------------------------------------------------------------------------------ //------------------------------------------------------------------------------
// Horizontal filter. // Horizontal filter.
@ -117,21 +74,18 @@ static void PredictLineC(const uint8_t* src, const uint8_t* pred,
static WEBP_INLINE void DoHorizontalFilter(const uint8_t* in, static WEBP_INLINE void DoHorizontalFilter(const uint8_t* in,
int width, int height, int stride, int width, int height, int stride,
int row, int num_rows, int row, int num_rows,
int inverse, uint8_t* out) { uint8_t* out) {
const uint8_t* preds;
const size_t start_offset = row * stride; const size_t start_offset = row * stride;
const int last_row = row + num_rows; const int last_row = row + num_rows;
SANITY_CHECK(in, out); SANITY_CHECK(in, out);
in += start_offset; in += start_offset;
out += start_offset; out += start_offset;
preds = inverse ? out : in;
if (row == 0) { if (row == 0) {
// Leftmost pixel is the same as input for topmost scanline. // Leftmost pixel is the same as input for topmost scanline.
out[0] = in[0]; out[0] = in[0];
PredictLineLeft(in + 1, out + 1, width - 1, inverse); PredictLineLeft(in + 1, out + 1, width - 1);
row = 1; row = 1;
preds += stride;
in += stride; in += stride;
out += stride; out += stride;
} }
@ -139,10 +93,9 @@ static WEBP_INLINE void DoHorizontalFilter(const uint8_t* in,
// Filter line-by-line. // Filter line-by-line.
while (row < last_row) { while (row < last_row) {
// Leftmost pixel is predicted from above. // Leftmost pixel is predicted from above.
PredictLineC(in, preds - stride, out, 1, inverse); out[0] = in[0] - in[-stride];
PredictLineLeft(in + 1, out + 1, width - 1, inverse); PredictLineLeft(in + 1, out + 1, width - 1);
++row; ++row;
preds += stride;
in += stride; in += stride;
out += stride; out += stride;
} }
@ -153,34 +106,27 @@ static WEBP_INLINE void DoHorizontalFilter(const uint8_t* in,
static WEBP_INLINE void DoVerticalFilter(const uint8_t* in, static WEBP_INLINE void DoVerticalFilter(const uint8_t* in,
int width, int height, int stride, int width, int height, int stride,
int row, int num_rows, int row, int num_rows, uint8_t* out) {
int inverse, uint8_t* out) {
const uint8_t* preds;
const size_t start_offset = row * stride; const size_t start_offset = row * stride;
const int last_row = row + num_rows; const int last_row = row + num_rows;
SANITY_CHECK(in, out); SANITY_CHECK(in, out);
in += start_offset; in += start_offset;
out += start_offset; out += start_offset;
preds = inverse ? out : in;
if (row == 0) { if (row == 0) {
// Very first top-left pixel is copied. // Very first top-left pixel is copied.
out[0] = in[0]; out[0] = in[0];
// Rest of top scan-line is left-predicted. // Rest of top scan-line is left-predicted.
PredictLineLeft(in + 1, out + 1, width - 1, inverse); PredictLineLeft(in + 1, out + 1, width - 1);
row = 1; row = 1;
in += stride; in += stride;
out += stride; out += stride;
} else {
// We are starting from in-between. Make sure 'preds' points to prev row.
preds -= stride;
} }
// Filter line-by-line. // Filter line-by-line.
while (row < last_row) { while (row < last_row) {
PredictLineTop(in, preds, out, width, inverse); PredictLineTop(in, in - stride, out, width);
++row; ++row;
preds += stride;
in += stride; in += stride;
out += stride; out += stride;
} }
@ -219,6 +165,101 @@ static void GradientPredictDirect(const uint8_t* const row,
} }
} }
static WEBP_INLINE void DoGradientFilter(const uint8_t* in,
int width, int height, int stride,
int row, int num_rows,
uint8_t* out) {
const size_t start_offset = row * stride;
const int last_row = row + num_rows;
SANITY_CHECK(in, out);
in += start_offset;
out += start_offset;
// left prediction for top scan-line
if (row == 0) {
out[0] = in[0];
PredictLineLeft(in + 1, out + 1, width - 1);
row = 1;
in += stride;
out += stride;
}
// Filter line-by-line.
while (row < last_row) {
out[0] = in[0] - in[-stride];
GradientPredictDirect(in + 1, in + 1 - stride, out + 1, width - 1);
++row;
in += stride;
out += stride;
}
}
#undef SANITY_CHECK
//------------------------------------------------------------------------------
static void HorizontalFilter(const uint8_t* data, int width, int height,
int stride, uint8_t* filtered_data) {
DoHorizontalFilter(data, width, height, stride, 0, height, filtered_data);
}
static void VerticalFilter(const uint8_t* data, int width, int height,
int stride, uint8_t* filtered_data) {
DoVerticalFilter(data, width, height, stride, 0, height, filtered_data);
}
static void GradientFilter(const uint8_t* data, int width, int height,
int stride, uint8_t* filtered_data) {
DoGradientFilter(data, width, height, stride, 0, height, filtered_data);
}
//------------------------------------------------------------------------------
// Inverse transforms
static void HorizontalUnfilter(const uint8_t* prev, const uint8_t* in,
uint8_t* out, int width) {
int i;
__m128i last;
out[0] = in[0] + (prev == NULL ? 0 : prev[0]);
if (width <= 1) return;
last = _mm_set_epi32(0, 0, 0, out[0]);
for (i = 1; i + 8 <= width; i += 8) {
const __m128i A0 = _mm_loadl_epi64((const __m128i*)(in + i));
const __m128i A1 = _mm_add_epi8(A0, last);
const __m128i A2 = _mm_slli_si128(A1, 1);
const __m128i A3 = _mm_add_epi8(A1, A2);
const __m128i A4 = _mm_slli_si128(A3, 2);
const __m128i A5 = _mm_add_epi8(A3, A4);
const __m128i A6 = _mm_slli_si128(A5, 4);
const __m128i A7 = _mm_add_epi8(A5, A6);
_mm_storel_epi64((__m128i*)(out + i), A7);
last = _mm_srli_epi64(A7, 56);
}
for (; i < width; ++i) out[i] = in[i] + out[i - 1];
}
static void VerticalUnfilter(const uint8_t* prev, const uint8_t* in,
uint8_t* out, int width) {
if (prev == NULL) {
HorizontalUnfilter(NULL, in, out, width);
} else {
int i;
const int max_pos = width & ~31;
assert(width >= 0);
for (i = 0; i < max_pos; i += 32) {
const __m128i A0 = _mm_loadu_si128((const __m128i*)&in[i + 0]);
const __m128i A1 = _mm_loadu_si128((const __m128i*)&in[i + 16]);
const __m128i B0 = _mm_loadu_si128((const __m128i*)&prev[i + 0]);
const __m128i B1 = _mm_loadu_si128((const __m128i*)&prev[i + 16]);
const __m128i C0 = _mm_add_epi8(A0, B0);
const __m128i C1 = _mm_add_epi8(A1, B1);
_mm_storeu_si128((__m128i*)&out[i + 0], C0);
_mm_storeu_si128((__m128i*)&out[i + 16], C1);
}
for (; i < width; ++i) out[i] = in[i] + prev[i];
}
}
static void GradientPredictInverse(const uint8_t* const in, static void GradientPredictInverse(const uint8_t* const in,
const uint8_t* const top, const uint8_t* const top,
uint8_t* const row, int length) { uint8_t* const row, int length) {
@ -232,25 +273,24 @@ static void GradientPredictInverse(const uint8_t* const in,
const __m128i tmp1 = _mm_loadl_epi64((const __m128i*)&top[i - 1]); const __m128i tmp1 = _mm_loadl_epi64((const __m128i*)&top[i - 1]);
const __m128i B = _mm_unpacklo_epi8(tmp0, zero); const __m128i B = _mm_unpacklo_epi8(tmp0, zero);
const __m128i C = _mm_unpacklo_epi8(tmp1, zero); const __m128i C = _mm_unpacklo_epi8(tmp1, zero);
const __m128i tmp2 = _mm_loadl_epi64((const __m128i*)&in[i]); const __m128i D = _mm_loadl_epi64((const __m128i*)&in[i]); // base input
const __m128i D = _mm_unpacklo_epi8(tmp2, zero); // base input
const __m128i E = _mm_sub_epi16(B, C); // unclipped gradient basis B - C const __m128i E = _mm_sub_epi16(B, C); // unclipped gradient basis B - C
__m128i out = zero; // accumulator for output __m128i out = zero; // accumulator for output
__m128i mask_hi = _mm_set_epi32(0, 0, 0, 0xff); __m128i mask_hi = _mm_set_epi32(0, 0, 0, 0xff);
int k = 8; int k = 8;
while (1) { while (1) {
const __m128i tmp3 = _mm_add_epi16(A, E); // delta = A + B - C const __m128i tmp3 = _mm_add_epi16(A, E); // delta = A + B - C
const __m128i tmp4 = _mm_min_epi16(tmp3, mask_hi); const __m128i tmp4 = _mm_packus_epi16(tmp3, zero); // saturate delta
const __m128i tmp5 = _mm_max_epi16(tmp4, zero); // clipped delta const __m128i tmp5 = _mm_add_epi8(tmp4, D); // add to in[]
const __m128i tmp6 = _mm_add_epi16(tmp5, D); // add to in[] values A = _mm_and_si128(tmp5, mask_hi); // 1-complement clip
A = _mm_and_si128(tmp6, mask_hi); // 1-complement clip
out = _mm_or_si128(out, A); // accumulate output out = _mm_or_si128(out, A); // accumulate output
if (--k == 0) break; if (--k == 0) break;
A = _mm_slli_si128(A, 2); // rotate left sample A = _mm_slli_si128(A, 1); // rotate left sample
mask_hi = _mm_slli_si128(mask_hi, 2); // rotate mask mask_hi = _mm_slli_si128(mask_hi, 1); // rotate mask
A = _mm_unpacklo_epi8(A, zero); // convert 8b->16b
} }
A = _mm_srli_si128(A, 14); // prepare left sample for next iteration A = _mm_srli_si128(A, 7); // prepare left sample for next iteration
_mm_storel_epi64((__m128i*)&row[i], _mm_packus_epi16(out, zero)); _mm_storel_epi64((__m128i*)&row[i], out);
} }
for (; i < length; ++i) { for (; i < length; ++i) {
row[i] = in[i] + GradientPredictorC(row[i - 1], top[i], top[i - 1]); row[i] = in[i] + GradientPredictorC(row[i - 1], top[i], top[i - 1]);
@ -258,76 +298,14 @@ static void GradientPredictInverse(const uint8_t* const in,
} }
} }
static WEBP_INLINE void DoGradientFilter(const uint8_t* in, static void GradientUnfilter(const uint8_t* prev, const uint8_t* in,
int width, int height, int stride, uint8_t* out, int width) {
int row, int num_rows, if (prev == NULL) {
int inverse, uint8_t* out) { HorizontalUnfilter(NULL, in, out, width);
const size_t start_offset = row * stride;
const int last_row = row + num_rows;
SANITY_CHECK(in, out);
in += start_offset;
out += start_offset;
// left prediction for top scan-line
if (row == 0) {
out[0] = in[0];
PredictLineLeft(in + 1, out + 1, width - 1, inverse);
row = 1;
in += stride;
out += stride;
}
// Filter line-by-line.
while (row < last_row) {
if (inverse) {
PredictLineC(in, out - stride, out, 1, inverse); // predict from above
GradientPredictInverse(in + 1, out + 1 - stride, out + 1, width - 1);
} else { } else {
PredictLineC(in, in - stride, out, 1, inverse); out[0] = in[0] + prev[0]; // predict from above
GradientPredictDirect(in + 1, in + 1 - stride, out + 1, width - 1); GradientPredictInverse(in + 1, prev + 1, out + 1, width - 1);
} }
++row;
in += stride;
out += stride;
}
}
#undef SANITY_CHECK
//------------------------------------------------------------------------------
static void HorizontalFilter(const uint8_t* data, int width, int height,
int stride, uint8_t* filtered_data) {
DoHorizontalFilter(data, width, height, stride, 0, height, 0, filtered_data);
}
static void VerticalFilter(const uint8_t* data, int width, int height,
int stride, uint8_t* filtered_data) {
DoVerticalFilter(data, width, height, stride, 0, height, 0, filtered_data);
}
static void GradientFilter(const uint8_t* data, int width, int height,
int stride, uint8_t* filtered_data) {
DoGradientFilter(data, width, height, stride, 0, height, 0, filtered_data);
}
//------------------------------------------------------------------------------
static void VerticalUnfilter(int width, int height, int stride, int row,
int num_rows, uint8_t* data) {
DoVerticalFilter(data, width, height, stride, row, num_rows, 1, data);
}
static void HorizontalUnfilter(int width, int height, int stride, int row,
int num_rows, uint8_t* data) {
DoHorizontalFilter(data, width, height, stride, row, num_rows, 1, data);
}
static void GradientUnfilter(int width, int height, int stride, int row,
int num_rows, uint8_t* data) {
DoGradientFilter(data, width, height, stride, row, num_rows, 1, data);
} }
//------------------------------------------------------------------------------ //------------------------------------------------------------------------------