diff options
| -rw-r--r-- | src/meh.h | 4 | ||||
| -rw-r--r-- | src/scale.c | 80 |
2 files changed, 76 insertions, 8 deletions
@@ -33,8 +33,8 @@ struct image{ /* scale */ -void scale(struct image *img, int width, int height, int bytesperline, char* __restrict__ newBuf); -void nearestscale(struct image *img, int width, int height, int bytesperline, char* __restrict__ newBuf); +void scale(struct image *img, unsigned int width, unsigned int height, unsigned int bytesperline, char* __restrict__ newBuf); +void nearestscale(struct image *img, unsigned int width, unsigned int height, unsigned int bytesperline, char* __restrict__ newBuf); /* XLib */ void setaspect(unsigned int w, unsigned int h); diff --git a/src/scale.c b/src/scale.c index 21fa505..6555af3 100644 --- a/src/scale.c +++ b/src/scale.c @@ -1,4 +1,6 @@ +#include <assert.h> +#include <string.h> #include <stdint.h> #include <sys/time.h> #include "meh.h" @@ -34,9 +36,64 @@ ibuf = &img->buf[y * img->bufheight / height * img->bufwidth * 3];\ ibufn = ibuf + dy; +/* + * Super sampling scale. Down only. + */ +static void superscale(struct image *img, unsigned int width, unsigned int height, unsigned int bytesperline, char* __restrict__ newBuf){ + uint32_t x, y, i; + unsigned char * __restrict__ ibuf; + ibuf = &img->buf[0]; + + TDEBUG_START + + int divx[bytesperline]; + int divy[bytesperline]; + memset(divx, 0, sizeof divx); + memset(divy, 0, sizeof divy); + for(x = 0; x < img->bufwidth; x++){ + divx[x * width / img->bufwidth]++; + } + for(y = 0; y < img->bufheight; y++){ + divy[y * height / img->bufheight]++; + } + + int xoff[img->bufwidth]; + for(x = 0; x < img->bufwidth; x++){ + xoff[x] = (x * width / img->bufwidth) * 3; + } -void scale(struct image *img, int width, int height, int bytesperline, char* __restrict__ newBuf){ - int x, y; + int tmp[width * 4]; + unsigned int y0; + for(y = 0; y < img->bufheight;){ + int ydiv = divy[y * height / img->bufheight]; + char * __restrict__ ydest = &newBuf[bytesperline * (y * height / img->bufheight)]; + memset(tmp, 0, sizeof tmp); + ibuf = &img->buf[y * img->bufwidth * 3]; + for(y0 = y; y < y0 + ydiv; y++){ + for(x = 0; x < img->bufwidth; x++){ + int * __restrict__ dest = tmp + xoff[x]; + for(i = 0; i < 3; i++){ + *dest++ += *ibuf++; + } + } + } + int * __restrict__ src = tmp; + for(x = 0; x < width; x++){ + ydest[2] = *src++ / ydiv / divx[x]; + ydest[1] = *src++ / ydiv / divx[x]; + ydest[0] = *src++ / ydiv / divx[x]; + ydest += 4; + } + } + + TDEBUG_END("superscale") +} + +/* + * Bilinear scale. Used for up only. + */ +static void bilinearscale(struct image *img, unsigned int width, unsigned int height, unsigned int bytesperline, char* __restrict__ newBuf){ + unsigned int x, y; const unsigned char * __restrict__ ibuf; const unsigned char * __restrict__ ibufn; const unsigned char * const bufend = &img->buf[img->bufwidth * img->bufheight * 3]; @@ -86,11 +143,22 @@ void scale(struct image *img, int width, int height, int bytesperline, char* __r y++; } - TDEBUG_END("scale") + TDEBUG_END("bilinearscale") +} + +void scale(struct image *img, unsigned int width, unsigned int height, unsigned int bytesperline, char* __restrict__ newBuf){ + if(width < img->bufwidth){ + superscale(img, width, height, bytesperline, newBuf); + }else{ + bilinearscale(img, width, height, bytesperline, newBuf); + } } -void nearestscale(struct image *img, int width, int height, int bytesperline, char* __restrict__ newBuf){ - int x, y; +/* + * Nearest neighbour. Fast up and down. + */ +void nearestscale(struct image *img, unsigned int width, unsigned int height, unsigned int bytesperline, char* __restrict__ newBuf){ + unsigned int x, y; unsigned char * __restrict__ ibuf; unsigned int jdy = bytesperline / 4 - width; unsigned int dx = (img->bufwidth << 10) / width; @@ -111,7 +179,7 @@ void nearestscale(struct image *img, int width, int height, int bytesperline, ch newBuf += jdy; } - TDEBUG_END("linearscale") + TDEBUG_END("nearestscale") } |