Changeset 2605 for libpipi/trunk/pipi/pixels.cTweet

Timestamp:

Jul 29, 2008, 1:01:29 AM (14 years ago)

Author:

Sam Hocevar

Message:

• Big API reorganisation. Now libpipi can transparently convert between colour spaces for a given image. For instance, if pipi_gaussian_blur is applied to a 32-bpp image, it is automatically converted to gamma-corrected 32-bit floats beforehands, then converted back to normal.
• TODO: clipping, regions of interest, more formats, getpixel macros...

File:

• libpipi/trunk/pipi/pixels.c (modified) (1 diff)

libpipi/trunk/pipi/pixels.c

@@ -32 +32 @@
 #define I2C(p) ((int)255.999*pow(((double)p), 1./2.2))
 
-int pipi_getgray(pipi_image_t const *img, int x, int y, int *g)
+/* Return a direct pointer to an image's pixels. */
+pipi_pixels_t *pipi_getpixels(pipi_image_t *img, pipi_format_t type)
 {
-    if(x < 0 || y < 0 || x >= img->width || y >= img->height)
+    size_t bytes = 0;
+    int x, y, i;
+
+    if(type < 0 || type >= PIPI_PIXELS_MAX)
+        return NULL;
+
+    if(img->last_modified == type)
+        return &img->p[type];
+
+    /* Allocate pixels if necessary */
+    if(!img->p[type].pixels)
     {
-        *g = 255;
-        return -1;
+        switch(type)
+        {
+        case PIPI_PIXELS_RGBA32:
+            bytes = img->w * img->h * 4 * sizeof(uint8_t);
+            break;
+        case PIPI_PIXELS_RGBA_F:
+            bytes = img->w * img->h * 4 * sizeof(float);
+            break;
+        default:
+            return NULL;
+        }
+
+        img->p[type].pixels = malloc(bytes);
     }
 
-    *g = (unsigned char)img->pixels[y * img->pitch + x * img->channels + 1];
+    /* Convert pixels */
+    if(img->last_modified == PIPI_PIXELS_RGBA32
+                  && type == PIPI_PIXELS_RGBA_F)
+    {
+        uint8_t *src = (uint8_t *)img->p[PIPI_PIXELS_RGBA32].pixels;
+        float *dest = (float *)img->p[type].pixels;
 
-    return 0;
+        for(y = 0; y < img->h; y++)
+            for(x = 0; x < img->w; x++)
+                for(i = 0; i < 4; i++)
+                    dest[4 * (y * img->w + x) + i]
+                        = C2I(src[4 * (y * img->w + x) + i]);
+    }
+    else if(img->last_modified == PIPI_PIXELS_RGBA_F
+                       && type == PIPI_PIXELS_RGBA32)
+    {
+        float *src = (float *)img->p[PIPI_PIXELS_RGBA_F].pixels;
+        uint8_t *dest = (uint8_t *)img->p[type].pixels;
+
+        for(y = 0; y < img->h; y++)
+            for(x = 0; x < img->w; x++)
+                for(i = 0; i < 4; i++)
+                    dest[4 * (y * img->w + x) + i]
+                        = I2C(src[4 * (y * img->w + x) + i]);
+    }
+    else
+    {
+        memset(img->p[type].pixels, 0, bytes);
+    }
+
+    img->last_modified = type;
+
+    return &img->p[type];
 }
 
-int pipi_getpixel(pipi_image_t const *img,
-                  int x, int y, double *r, double *g, double *b)
-{
-    uint8_t *pixel;
-
-    if(x < 0) x = 0;
-    else if(x >= img->width) x = img->width - 1;
-
-    if(y < 0) y = 0;
-    else if(y >= img->height) y = img->height - 1;
-
-    pixel = img->pixels + y * img->pitch + x * img->channels;
-
-    *b = C2I((unsigned char)pixel[0]);
-    *g = C2I((unsigned char)pixel[1]);
-    *r = C2I((unsigned char)pixel[2]);
-
-    return 0;
-}
-
-int pipi_setpixel(pipi_image_t *img, int x, int y, double r, double g, double b)
-{
-    uint8_t *pixel;
-
-    if(x < 0 || y < 0 || x >= img->width || y >= img->height)
-        return -1;
-
-    pixel = img->pixels + y * img->pitch + x * img->channels;
-
-    pixel[0] = I2C(b);
-    pixel[1] = I2C(g);
-    pixel[2] = I2C(r);
-
-    return 0;
-}
-