Pillow/libImaging/Storage.c
2017-01-29 07:20:44 +01:00

458 lines
12 KiB
C

/*
* The Python Imaging Library
* $Id$
*
* imaging storage object
*
* This baseline implementation is designed to efficiently handle
* large images, provided they fit into the available memory.
*
* history:
* 1995-06-15 fl Created
* 1995-09-12 fl Updated API, compiles silently under ANSI C++
* 1995-11-26 fl Compiles silently under Borland 4.5 as well
* 1996-05-05 fl Correctly test status from Prologue
* 1997-05-12 fl Increased THRESHOLD (to speed up Tk interface)
* 1997-05-30 fl Added support for floating point images
* 1997-11-17 fl Added support for "RGBX" images
* 1998-01-11 fl Added support for integer images
* 1998-03-05 fl Exported Prologue/Epilogue functions
* 1998-07-01 fl Added basic "YCrCb" support
* 1998-07-03 fl Attach palette in prologue for "P" images
* 1998-07-09 hk Don't report MemoryError on zero-size images
* 1998-07-12 fl Change "YCrCb" to "YCbCr" (!)
* 1998-10-26 fl Added "I;16" and "I;16B" storage modes (experimental)
* 1998-12-29 fl Fixed allocation bug caused by previous fix
* 1999-02-03 fl Added "RGBa" and "BGR" modes (experimental)
* 2001-04-22 fl Fixed potential memory leak in ImagingCopyInfo
* 2003-09-26 fl Added "LA" and "PA" modes (experimental)
* 2005-10-02 fl Added image counter
*
* Copyright (c) 1998-2005 by Secret Labs AB
* Copyright (c) 1995-2005 by Fredrik Lundh
*
* See the README file for information on usage and redistribution.
*/
#include "Imaging.h"
#include <string.h>
int ImagingNewCount = 0;
/* --------------------------------------------------------------------
* Standard image object.
*/
Imaging
ImagingNewPrologueSubtype(const char *mode, int xsize, int ysize,
int size)
{
Imaging im;
ImagingSectionCookie cookie;
im = (Imaging) calloc(1, size);
if (!im)
return (Imaging) ImagingError_MemoryError();
/* linesize overflow check, roughly the current largest space req'd */
if (xsize > (INT_MAX / 4) - 1) {
return (Imaging) ImagingError_MemoryError();
}
/* Setup image descriptor */
im->xsize = xsize;
im->ysize = ysize;
im->type = IMAGING_TYPE_UINT8;
if (strcmp(mode, "1") == 0) {
/* 1-bit images */
im->bands = im->pixelsize = 1;
im->linesize = xsize;
} else if (strcmp(mode, "P") == 0) {
/* 8-bit palette mapped images */
im->bands = im->pixelsize = 1;
im->linesize = xsize;
im->palette = ImagingPaletteNew("RGB");
} else if (strcmp(mode, "PA") == 0) {
/* 8-bit palette with alpha */
im->bands = 2;
im->pixelsize = 4; /* store in image32 memory */
im->linesize = xsize * 4;
im->palette = ImagingPaletteNew("RGB");
} else if (strcmp(mode, "L") == 0) {
/* 8-bit greyscale (luminance) images */
im->bands = im->pixelsize = 1;
im->linesize = xsize;
} else if (strcmp(mode, "LA") == 0) {
/* 8-bit greyscale (luminance) with alpha */
im->bands = 2;
im->pixelsize = 4; /* store in image32 memory */
im->linesize = xsize * 4;
} else if (strcmp(mode, "La") == 0) {
/* 8-bit greyscale (luminance) with premultiplied alpha */
im->bands = 2;
im->pixelsize = 4; /* store in image32 memory */
im->linesize = xsize * 4;
} else if (strcmp(mode, "F") == 0) {
/* 32-bit floating point images */
im->bands = 1;
im->pixelsize = 4;
im->linesize = xsize * 4;
im->type = IMAGING_TYPE_FLOAT32;
} else if (strcmp(mode, "I") == 0) {
/* 32-bit integer images */
im->bands = 1;
im->pixelsize = 4;
im->linesize = xsize * 4;
im->type = IMAGING_TYPE_INT32;
} else if (strcmp(mode, "I;16") == 0 || strcmp(mode, "I;16L") == 0 \
|| strcmp(mode, "I;16B") == 0 || strcmp(mode, "I;16N") == 0) {
/* EXPERIMENTAL */
/* 16-bit raw integer images */
im->bands = 1;
im->pixelsize = 2;
im->linesize = xsize * 2;
im->type = IMAGING_TYPE_SPECIAL;
} else if (strcmp(mode, "RGB") == 0) {
/* 24-bit true colour images */
im->bands = 3;
im->pixelsize = 4;
im->linesize = xsize * 4;
} else if (strcmp(mode, "BGR;15") == 0) {
/* EXPERIMENTAL */
/* 15-bit true colour */
im->bands = 1;
im->pixelsize = 2;
im->linesize = (xsize*2 + 3) & -4;
im->type = IMAGING_TYPE_SPECIAL;
} else if (strcmp(mode, "BGR;16") == 0) {
/* EXPERIMENTAL */
/* 16-bit reversed true colour */
im->bands = 1;
im->pixelsize = 2;
im->linesize = (xsize*2 + 3) & -4;
im->type = IMAGING_TYPE_SPECIAL;
} else if (strcmp(mode, "BGR;24") == 0) {
/* EXPERIMENTAL */
/* 24-bit reversed true colour */
im->bands = 1;
im->pixelsize = 3;
im->linesize = (xsize*3 + 3) & -4;
im->type = IMAGING_TYPE_SPECIAL;
} else if (strcmp(mode, "BGR;32") == 0) {
/* EXPERIMENTAL */
/* 32-bit reversed true colour */
im->bands = 1;
im->pixelsize = 4;
im->linesize = (xsize*4 + 3) & -4;
im->type = IMAGING_TYPE_SPECIAL;
} else if (strcmp(mode, "RGBX") == 0) {
/* 32-bit true colour images with padding */
im->bands = im->pixelsize = 4;
im->linesize = xsize * 4;
} else if (strcmp(mode, "RGBA") == 0) {
/* 32-bit true colour images with alpha */
im->bands = im->pixelsize = 4;
im->linesize = xsize * 4;
} else if (strcmp(mode, "RGBa") == 0) {
/* EXPERIMENTAL */
/* 32-bit true colour images with premultiplied alpha */
im->bands = im->pixelsize = 4;
im->linesize = xsize * 4;
} else if (strcmp(mode, "CMYK") == 0) {
/* 32-bit colour separation */
im->bands = im->pixelsize = 4;
im->linesize = xsize * 4;
} else if (strcmp(mode, "YCbCr") == 0) {
/* 24-bit video format */
im->bands = 3;
im->pixelsize = 4;
im->linesize = xsize * 4;
} else if (strcmp(mode, "LAB") == 0) {
/* 24-bit color, luminance, + 2 color channels */
/* L is uint8, a,b are int8 */
im->bands = 3;
im->pixelsize = 4;
im->linesize = xsize * 4;
} else if (strcmp(mode, "HSV") == 0) {
/* 24-bit color, luminance, + 2 color channels */
/* L is uint8, a,b are int8 */
im->bands = 3;
im->pixelsize = 4;
im->linesize = xsize * 4;
} else {
free(im);
return (Imaging) ImagingError_ValueError("unrecognized mode");
}
/* Setup image descriptor */
strcpy(im->mode, mode);
ImagingSectionEnter(&cookie);
/* Pointer array (allocate at least one line, to avoid MemoryError
exceptions on platforms where calloc(0, x) returns NULL) */
im->image = (char **) calloc((ysize > 0) ? ysize : 1, sizeof(void *));
ImagingSectionLeave(&cookie);
if (!im->image) {
free(im);
return (Imaging) ImagingError_MemoryError();
}
ImagingNewCount++;
return im;
}
Imaging
ImagingNewPrologue(const char *mode, int xsize, int ysize)
{
return ImagingNewPrologueSubtype(
mode, xsize, ysize, sizeof(struct ImagingMemoryInstance)
);
}
Imaging
ImagingNewEpilogue(Imaging im)
{
/* If the raster data allocator didn't setup a destructor,
assume that it couldn't allocate the required amount of
memory. */
if (!im->destroy)
return (Imaging) ImagingError_MemoryError();
/* Initialize alias pointers to pixel data. */
switch (im->pixelsize) {
case 1: case 2: case 3:
im->image8 = (UINT8 **) im->image;
break;
case 4:
im->image32 = (INT32 **) im->image;
break;
}
return im;
}
void
ImagingDelete(Imaging im)
{
if (!im)
return;
if (im->palette)
ImagingPaletteDelete(im->palette);
if (im->destroy)
im->destroy(im);
if (im->image)
free(im->image);
free(im);
}
/* Array Storage Type */
/* ------------------ */
/* Allocate image as an array of line buffers. */
static void
ImagingDestroyArray(Imaging im)
{
int y;
if (im->image)
for (y = 0; y < im->ysize; y++)
if (im->image[y])
free(im->image[y]);
}
Imaging
ImagingNewArray(const char *mode, int xsize, int ysize)
{
Imaging im;
ImagingSectionCookie cookie;
int y;
char* p;
im = ImagingNewPrologue(mode, xsize, ysize);
if (!im)
return NULL;
ImagingSectionEnter(&cookie);
/* Allocate image as an array of lines */
for (y = 0; y < im->ysize; y++) {
/* malloc check linesize checked in prologue */
p = (char *) calloc(1, im->linesize);
if (!p) {
ImagingDestroyArray(im);
break;
}
im->image[y] = p;
}
ImagingSectionLeave(&cookie);
if (y == im->ysize)
im->destroy = ImagingDestroyArray;
return ImagingNewEpilogue(im);
}
/* Block Storage Type */
/* ------------------ */
/* Allocate image as a single block. */
static void
ImagingDestroyBlock(Imaging im)
{
if (im->block)
free(im->block);
}
Imaging
ImagingNewBlock(const char *mode, int xsize, int ysize)
{
Imaging im;
Py_ssize_t y, i;
im = ImagingNewPrologue(mode, xsize, ysize);
if (!im)
return NULL;
/* We shouldn't overflow, since the threshold defined
below says that we're only going to allocate max 4M
here before going to the array allocator. Check anyway.
*/
if (im->linesize &&
im->ysize > INT_MAX / im->linesize) {
/* punt if we're going to overflow */
return NULL;
}
if (im->ysize * im->linesize <= 0) {
/* some platforms return NULL for malloc(0); this fix
prevents MemoryError on zero-sized images on such
platforms */
im->block = (char *) malloc(1);
} else {
/* malloc check ok, overflow check above */
im->block = (char *) calloc(im->ysize, im->linesize);
}
if (im->block) {
for (y = i = 0; y < im->ysize; y++) {
im->image[y] = im->block + i;
i += im->linesize;
}
im->destroy = ImagingDestroyBlock;
}
return ImagingNewEpilogue(im);
}
/* --------------------------------------------------------------------
* Create a new, internally allocated, image.
*/
#if defined(IMAGING_SMALL_MODEL)
#define THRESHOLD 16384L
#else
#define THRESHOLD (2048*2048*4L)
#endif
Imaging
ImagingNew(const char* mode, int xsize, int ysize)
{
int bytes;
Imaging im;
if (strcmp(mode, "") == 0)
return (Imaging) ImagingError_ValueError("empty mode");
if (strlen(mode) == 1) {
if (mode[0] == 'F' || mode[0] == 'I')
bytes = 4;
else
bytes = 1;
} else
bytes = strlen(mode); /* close enough */
if (xsize < 0 || ysize < 0) {
return (Imaging) ImagingError_ValueError("bad image size");
}
if ((int64_t) xsize * (int64_t) ysize <= THRESHOLD / bytes) {
im = ImagingNewBlock(mode, xsize, ysize);
if (im)
return im;
/* assume memory error; try allocating in array mode instead */
ImagingError_Clear();
}
return ImagingNewArray(mode, xsize, ysize);
}
Imaging
ImagingNew2(const char* mode, Imaging imOut, Imaging imIn)
{
/* allocate or validate output image */
if (imOut) {
/* make sure images match */
if (strcmp(imOut->mode, mode) != 0
|| imOut->xsize != imIn->xsize
|| imOut->ysize != imIn->ysize) {
return ImagingError_Mismatch();
}
} else {
/* create new image */
imOut = ImagingNew(mode, imIn->xsize, imIn->ysize);
if (!imOut)
return NULL;
}
return imOut;
}
void
ImagingCopyInfo(Imaging destination, Imaging source)
{
if (source->palette) {
if (destination->palette)
ImagingPaletteDelete(destination->palette);
destination->palette = ImagingPaletteDuplicate(source->palette);
}
}