From 3eacee8158033eb4090294ee4349e9ee8b666330 Mon Sep 17 00:00:00 2001 From: Urvang Joshi Date: Tue, 20 Mar 2012 10:59:22 +0000 Subject: [PATCH] Move rescaler methods out of io.c. (cherry picked from commit b5e9db1824f6efbe0bfb87e94b8d6e88a7973ef7) --- src/dec/io.c | 231 +++++++++--------------------------------------- src/dec/webp.c | 140 +++++++++++++++++++++++++++++ src/dec/webpi.h | 19 ++++ 3 files changed, 202 insertions(+), 188 deletions(-) diff --git a/src/dec/io.c b/src/dec/io.c index 84a0882c..9226760b 100644 --- a/src/dec/io.c +++ b/src/dec/io.c @@ -228,98 +228,6 @@ static int EmitAlphaRGBA4444(const VP8Io* const io, WebPDecParams* const p) { return 0; } -//------------------------------------------------------------------------------ -// Simple picture rescaler - -// TODO(skal): start a common library for encoder and decoder, and factorize -// this code in. - -#define RFIX 30 -#define MULT(x,y) (((int64_t)(x) * (y) + (1 << (RFIX - 1))) >> RFIX) - -static void InitRescaler(WebPRescaler* const wrk, - int src_width, int src_height, - uint8_t* dst, - int dst_width, int dst_height, int dst_stride, - int x_add, int x_sub, int y_add, int y_sub, - int32_t* work) { - wrk->x_expand = (src_width < dst_width); - wrk->src_width = src_width; - wrk->src_height = src_height; - wrk->dst_width = dst_width; - wrk->dst_height = dst_height; - wrk->dst = dst; - wrk->dst_stride = dst_stride; - // for 'x_expand', we use bilinear interpolation - wrk->x_add = wrk->x_expand ? (x_sub - 1) : x_add - x_sub; - wrk->x_sub = wrk->x_expand ? (x_add - 1) : x_sub; - wrk->y_accum = y_add; - wrk->y_add = y_add; - wrk->y_sub = y_sub; - wrk->fx_scale = (1 << RFIX) / x_sub; - wrk->fy_scale = (1 << RFIX) / y_sub; - wrk->fxy_scale = wrk->x_expand ? - ((int64_t)dst_height << RFIX) / (x_sub * src_height) : - ((int64_t)dst_height << RFIX) / (x_add * src_height); - wrk->irow = work; - wrk->frow = work + dst_width; -} - -static WEBP_INLINE void ImportRow(const uint8_t* const src, - WebPRescaler* const wrk) { - int x_in = 0; - int x_out; - int accum = 0; - if (!wrk->x_expand) { - int sum = 0; - for (x_out = 0; x_out < wrk->dst_width; ++x_out) { - accum += wrk->x_add; - for (; accum > 0; accum -= wrk->x_sub) { - sum += src[x_in++]; - } - { // Emit next horizontal pixel. - const int32_t base = src[x_in++]; - const int32_t frac = base * (-accum); - wrk->frow[x_out] = (sum + base) * wrk->x_sub - frac; - // fresh fractional start for next pixel - sum = (int)MULT(frac, wrk->fx_scale); - } - } - } else { // simple bilinear interpolation - int left = src[0], right = src[0]; - for (x_out = 0; x_out < wrk->dst_width; ++x_out) { - if (accum < 0) { - left = right; - right = src[++x_in]; - accum += wrk->x_add; - } - wrk->frow[x_out] = right * wrk->x_add + (left - right) * accum; - accum -= wrk->x_sub; - } - } - // Accumulate the new row's contribution - for (x_out = 0; x_out < wrk->dst_width; ++x_out) { - wrk->irow[x_out] += wrk->frow[x_out]; - } -} - -static void ExportRow(WebPRescaler* const wrk) { - int x_out; - const int yscale = wrk->fy_scale * (-wrk->y_accum); - assert(wrk->y_accum <= 0); - for (x_out = 0; x_out < wrk->dst_width; ++x_out) { - const int frac = (int)MULT(wrk->frow[x_out], yscale); - const int v = (int)MULT(wrk->irow[x_out] - frac, wrk->fxy_scale); - wrk->dst[x_out] = (!(v & ~0xff)) ? v : (v < 0) ? 0 : 255; - wrk->irow[x_out] = frac; // new fractional start - } - wrk->y_accum += wrk->y_add; - wrk->dst += wrk->dst_stride; -} - -#undef MULT -#undef RFIX - //------------------------------------------------------------------------------ // YUV rescaling (no final RGB conversion needed) @@ -327,11 +235,11 @@ static int Rescale(const uint8_t* src, int src_stride, int new_lines, WebPRescaler* const wrk) { int num_lines_out = 0; while (new_lines-- > 0) { // import new contribution of one source row. - ImportRow(src, wrk); + WebPRescalerImportRow(src, wrk); src += src_stride; wrk->y_accum -= wrk->y_sub; while (wrk->y_accum <= 0) { // emit output row(s) - ExportRow(wrk); + WebPRescalerExportRow(wrk); ++num_lines_out; } } @@ -382,26 +290,26 @@ static int InitYUVRescaler(const VP8Io* const io, WebPDecParams* const p) { return 0; // memory error } work = (int32_t*)p->memory; - InitRescaler(&p->scaler_y, io->mb_w, io->mb_h, - buf->y, out_width, out_height, buf->y_stride, - io->mb_w, out_width, io->mb_h, out_height, - work); - InitRescaler(&p->scaler_u, uv_in_width, uv_in_height, - buf->u, uv_out_width, uv_out_height, buf->u_stride, - uv_in_width, uv_out_width, - uv_in_height, uv_out_height, - work + work_size); - InitRescaler(&p->scaler_v, uv_in_width, uv_in_height, - buf->v, uv_out_width, uv_out_height, buf->v_stride, - uv_in_width, uv_out_width, - uv_in_height, uv_out_height, - work + work_size + uv_work_size); + WebPRescalerInit(&p->scaler_y, io->mb_w, io->mb_h, + buf->y, out_width, out_height, buf->y_stride, + io->mb_w, out_width, io->mb_h, out_height, + work); + WebPRescalerInit(&p->scaler_u, uv_in_width, uv_in_height, + buf->u, uv_out_width, uv_out_height, buf->u_stride, + uv_in_width, uv_out_width, + uv_in_height, uv_out_height, + work + work_size); + WebPRescalerInit(&p->scaler_v, uv_in_width, uv_in_height, + buf->v, uv_out_width, uv_out_height, buf->v_stride, + uv_in_width, uv_out_width, + uv_in_height, uv_out_height, + work + work_size + uv_work_size); p->emit = EmitRescaledYUV; if (has_alpha) { - InitRescaler(&p->scaler_a, io->mb_w, io->mb_h, - buf->a, out_width, out_height, buf->a_stride, - io->mb_w, out_width, io->mb_h, out_height, - work + work_size + 2 * uv_work_size); + WebPRescalerInit(&p->scaler_a, io->mb_w, io->mb_h, + buf->a, out_width, out_height, buf->a_stride, + io->mb_w, out_width, io->mb_h, out_height, + work + work_size + 2 * uv_work_size); p->emit_alpha = EmitRescaledAlphaYUV; } return 1; @@ -416,7 +324,7 @@ static int Import(const uint8_t* src, int src_stride, int new_lines, WebPRescaler* const wrk) { int num_lines_in = 0; while (num_lines_in < new_lines && wrk->y_accum > 0) { - ImportRow(src, wrk); + WebPRescalerImportRow(src, wrk); src += src_stride; ++num_lines_in; wrk->y_accum -= wrk->y_sub; @@ -435,9 +343,9 @@ static int ExportRGB(WebPDecParams* const p, int y_pos) { while (p->scaler_y.y_accum <= 0 && p->scaler_u.y_accum <= 0) { assert(p->last_y + y_pos + num_lines_out < p->output->height); assert(p->scaler_u.y_accum == p->scaler_v.y_accum); - ExportRow(&p->scaler_y); - ExportRow(&p->scaler_u); - ExportRow(&p->scaler_v); + WebPRescalerExportRow(&p->scaler_y); + WebPRescalerExportRow(&p->scaler_u); + WebPRescalerExportRow(&p->scaler_v); convert(p->scaler_y.dst, p->scaler_u.dst, p->scaler_v.dst, dst, p->scaler_y.dst_width); dst += buf->stride; @@ -475,7 +383,7 @@ static int ExportAlpha(WebPDecParams* const p, int y_pos) { while (p->scaler_a.y_accum <= 0) { int i; assert(p->last_y + y_pos + num_lines_out < p->output->height); - ExportRow(&p->scaler_a); + WebPRescalerExportRow(&p->scaler_a); for (i = 0; i < p->scaler_a.dst_width; ++i) { dst[4 * i] = p->scaler_a.dst[i]; } @@ -492,7 +400,7 @@ static int ExportAlphaRGBA4444(WebPDecParams* const p, int y_pos) { while (p->scaler_a.y_accum <= 0) { int i; assert(p->last_y + y_pos + num_lines_out < p->output->height); - ExportRow(&p->scaler_a); + WebPRescalerExportRow(&p->scaler_a); for (i = 0; i < p->scaler_a.dst_width; ++i) { // Fill in the alpha value (converted to 4 bits). const uint32_t alpha_val = clip((p->scaler_a.dst[i] + 8) >> 4, 15); @@ -543,25 +451,25 @@ static int InitRGBRescaler(const VP8Io* const io, WebPDecParams* const p) { } work = (int32_t*)p->memory; tmp = (uint8_t*)(work + tmp_size1); - InitRescaler(&p->scaler_y, io->mb_w, io->mb_h, - tmp + 0 * out_width, out_width, out_height, 0, - io->mb_w, out_width, io->mb_h, out_height, - work + 0 * work_size); - InitRescaler(&p->scaler_u, uv_in_width, uv_in_height, - tmp + 1 * out_width, out_width, out_height, 0, - io->mb_w, 2 * out_width, io->mb_h, 2 * out_height, - work + 1 * work_size); - InitRescaler(&p->scaler_v, uv_in_width, uv_in_height, - tmp + 2 * out_width, out_width, out_height, 0, - io->mb_w, 2 * out_width, io->mb_h, 2 * out_height, - work + 2 * work_size); + WebPRescalerInit(&p->scaler_y, io->mb_w, io->mb_h, + tmp + 0 * out_width, out_width, out_height, 0, + io->mb_w, out_width, io->mb_h, out_height, + work + 0 * work_size); + WebPRescalerInit(&p->scaler_u, uv_in_width, uv_in_height, + tmp + 1 * out_width, out_width, out_height, 0, + io->mb_w, 2 * out_width, io->mb_h, 2 * out_height, + work + 1 * work_size); + WebPRescalerInit(&p->scaler_v, uv_in_width, uv_in_height, + tmp + 2 * out_width, out_width, out_height, 0, + io->mb_w, 2 * out_width, io->mb_h, 2 * out_height, + work + 2 * work_size); p->emit = EmitRescaledRGB; if (has_alpha) { - InitRescaler(&p->scaler_a, io->mb_w, io->mb_h, - tmp + 3 * out_width, out_width, out_height, 0, - io->mb_w, out_width, io->mb_h, out_height, - work + 3 * work_size); + WebPRescalerInit(&p->scaler_a, io->mb_w, io->mb_h, + tmp + 3 * out_width, out_width, out_height, 0, + io->mb_w, out_width, io->mb_h, out_height, + work + 3 * work_size); p->emit_alpha = EmitRescaledAlphaRGB; } return 1; @@ -570,59 +478,6 @@ static int InitRGBRescaler(const VP8Io* const io, WebPDecParams* const p) { //------------------------------------------------------------------------------ // Default custom functions -// Setup crop_xxx fields, mb_w and mb_h -static int InitFromOptions(const WebPDecoderOptions* const options, - VP8Io* const io) { - const int W = io->width; - const int H = io->height; - int x = 0, y = 0, w = W, h = H; - - // Cropping - io->use_cropping = (options != NULL) && (options->use_cropping > 0); - if (io->use_cropping) { - w = options->crop_width; - h = options->crop_height; - // TODO(skal): take colorspace into account. Don't assume YUV420. - x = options->crop_left & ~1; - y = options->crop_top & ~1; - if (x < 0 || y < 0 || w <= 0 || h <= 0 || x + w > W || y + h > H) { - return 0; // out of frame boundary error - } - } - io->crop_left = x; - io->crop_top = y; - io->crop_right = x + w; - io->crop_bottom = y + h; - io->mb_w = w; - io->mb_h = h; - - // Scaling - io->use_scaling = (options != NULL) && (options->use_scaling > 0); - if (io->use_scaling) { - if (options->scaled_width <= 0 || options->scaled_height <= 0) { - return 0; - } - io->scaled_width = options->scaled_width; - io->scaled_height = options->scaled_height; - } - - // Filter - io->bypass_filtering = options && options->bypass_filtering; - - // Fancy upsampler -#ifdef FANCY_UPSAMPLING - io->fancy_upsampling = (options == NULL) || (!options->no_fancy_upsampling); -#endif - - if (io->use_scaling) { - // disable filter (only for large downscaling ratio). - io->bypass_filtering = (io->scaled_width < W * 3 / 4) && - (io->scaled_height < H * 3 / 4); - io->fancy_upsampling = 0; - } - return 1; -} - static int CustomSetup(VP8Io* io) { WebPDecParams* const p = (WebPDecParams*)io->opaque; const int is_rgb = (p->output->colorspace < MODE_YUV); @@ -630,7 +485,7 @@ static int CustomSetup(VP8Io* io) { p->memory = NULL; p->emit = NULL; p->emit_alpha = NULL; - if (!InitFromOptions(p->options, io)) { + if (!WebPIoInitFromOptions(p->options, io)) { return 0; } diff --git a/src/dec/webp.c b/src/dec/webp.c index b9024969..9faf6e0a 100644 --- a/src/dec/webp.c +++ b/src/dec/webp.c @@ -609,6 +609,146 @@ VP8StatusCode WebPDecode(const uint8_t* data, uint32_t data_size, return status; } +//------------------------------------------------------------------------------ +// Simple picture rescaler + +int WebPIoInitFromOptions(const WebPDecoderOptions* const options, + VP8Io* const io) { + const int W = io->width; + const int H = io->height; + int x = 0, y = 0, w = W, h = H; + + // Cropping + io->use_cropping = (options != NULL) && (options->use_cropping > 0); + if (io->use_cropping) { + w = options->crop_width; + h = options->crop_height; + // TODO(skal): take colorspace into account. Don't assume YUV420. + x = options->crop_left & ~1; + y = options->crop_top & ~1; + if (x < 0 || y < 0 || w <= 0 || h <= 0 || x + w > W || y + h > H) { + return 0; // out of frame boundary error + } + } + io->crop_left = x; + io->crop_top = y; + io->crop_right = x + w; + io->crop_bottom = y + h; + io->mb_w = w; + io->mb_h = h; + + // Scaling + io->use_scaling = (options != NULL) && (options->use_scaling > 0); + if (io->use_scaling) { + if (options->scaled_width <= 0 || options->scaled_height <= 0) { + return 0; + } + io->scaled_width = options->scaled_width; + io->scaled_height = options->scaled_height; + } + + // Filter + io->bypass_filtering = options && options->bypass_filtering; + + // Fancy upsampler +#ifdef FANCY_UPSAMPLING + io->fancy_upsampling = (options == NULL) || (!options->no_fancy_upsampling); +#endif + + if (io->use_scaling) { + // disable filter (only for large downscaling ratio). + io->bypass_filtering = (io->scaled_width < W * 3 / 4) && + (io->scaled_height < H * 3 / 4); + io->fancy_upsampling = 0; + } + return 1; +} + +#define RFIX 30 +#define MULT(x,y) (((int64_t)(x) * (y) + (1 << (RFIX - 1))) >> RFIX) + +void WebPRescalerInit(WebPRescaler* const wrk, int src_width, int src_height, + uint8_t* dst, int dst_width, int dst_height, + int dst_stride, int x_add, int x_sub, int y_add, + int y_sub, int32_t* work) { + wrk->x_expand = (src_width < dst_width); + wrk->src_width = src_width; + wrk->src_height = src_height; + wrk->dst_width = dst_width; + wrk->dst_height = dst_height; + wrk->dst = dst; + wrk->dst_stride = dst_stride; + // for 'x_expand', we use bilinear interpolation + wrk->x_add = wrk->x_expand ? (x_sub - 1) : x_add - x_sub; + wrk->x_sub = wrk->x_expand ? (x_add - 1) : x_sub; + wrk->y_accum = y_add; + wrk->y_add = y_add; + wrk->y_sub = y_sub; + wrk->fx_scale = (1 << RFIX) / x_sub; + wrk->fy_scale = (1 << RFIX) / y_sub; + wrk->fxy_scale = wrk->x_expand ? + ((int64_t)dst_height << RFIX) / (x_sub * src_height) : + ((int64_t)dst_height << RFIX) / (x_add * src_height); + wrk->irow = work; + wrk->frow = work + dst_width; +} + +void WebPRescalerImportRow(const uint8_t* const src, WebPRescaler* const wrk) { + int x_in = 0; + int x_out; + int accum = 0; + if (!wrk->x_expand) { + int sum = 0; + for (x_out = 0; x_out < wrk->dst_width; ++x_out) { + accum += wrk->x_add; + for (; accum > 0; accum -= wrk->x_sub) { + sum += src[x_in++]; + } + { // Emit next horizontal pixel. + const int32_t base = src[x_in++]; + const int32_t frac = base * (-accum); + wrk->frow[x_out] = (sum + base) * wrk->x_sub - frac; + // fresh fractional start for next pixel + sum = (int)MULT(frac, wrk->fx_scale); + } + } + } else { // simple bilinear interpolation + int left = src[0], right = src[0]; + for (x_out = 0; x_out < wrk->dst_width; ++x_out) { + if (accum < 0) { + left = right; + right = src[++x_in]; + accum += wrk->x_add; + } + wrk->frow[x_out] = right * wrk->x_add + (left - right) * accum; + accum -= wrk->x_sub; + } + } + // Accumulate the new row's contribution + for (x_out = 0; x_out < wrk->dst_width; ++x_out) { + wrk->irow[x_out] += wrk->frow[x_out]; + } +} + +void WebPRescalerExportRow(WebPRescaler* const wrk) { + int x_out; + const int yscale = wrk->fy_scale * (-wrk->y_accum); + assert(wrk->y_accum <= 0); + for (x_out = 0; x_out < wrk->dst_width; ++x_out) { + const int frac = (int)MULT(wrk->frow[x_out], yscale); + const int v = (int)MULT(wrk->irow[x_out] - frac, wrk->fxy_scale); + wrk->dst[x_out] = (!(v & ~0xff)) ? v : (v < 0) ? 0 : 255; + wrk->irow[x_out] = frac; // new fractional start + } + wrk->y_accum += wrk->y_add; + wrk->dst += wrk->dst_stride; +} + +#undef MULT +#undef RFIX + +//------------------------------------------------------------------------------ + #if defined(__cplusplus) || defined(c_plusplus) } // extern "C" #endif diff --git a/src/dec/webpi.h b/src/dec/webpi.h index 83b6ec30..d78a1b5e 100644 --- a/src/dec/webpi.h +++ b/src/dec/webpi.h @@ -159,6 +159,25 @@ void WebPCopyDecBuffer(const WebPDecBuffer* const src, // Copy and transfer ownership from src to dst (beware of parameter order!) void WebPGrabDecBuffer(WebPDecBuffer* const src, WebPDecBuffer* const dst); +//------------------------------------------------------------------------------ +// Cropping and rescaling. + +// Setup crop_xxx fields, mb_w and mb_h +int WebPIoInitFromOptions(const WebPDecoderOptions* const options, + VP8Io* const io); + +// Initialize a rescaler given scratch area 'work' and dimensions of src & dst. +void WebPRescalerInit(WebPRescaler* const wrk, int src_width, int src_height, + uint8_t* dst, int dst_width, int dst_height, + int dst_stride, int x_add, int x_sub, int y_add, + int y_sub, int32_t* work); + +// Import a row of data and save its contribution in the rescaler. +void WebPRescalerImportRow(const uint8_t* const src, WebPRescaler* const wrk); + +// Export a row from rescaler. +void WebPRescalerExportRow(WebPRescaler* const wrk); + //------------------------------------------------------------------------------ #if defined(__cplusplus) || defined(c_plusplus)