746407bfbe
Signed-off-by: Alexander Shiyan <shc_work@mail.ru> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
815 lines
25 KiB
C
815 lines
25 KiB
C
// picoPNG version 20080503 (cleaned up and ported to c by kaitek)
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// Copyright (c) 2005-2008 Lode Vandevenne
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//
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// This software is provided 'as-is', without any express or implied
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// warranty. In no event will the authors be held liable for any damages
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// arising from the use of this software.
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//
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// Permission is granted to anyone to use this software for any purpose,
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// including commercial applications, and to alter it and redistribute it
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// freely, subject to the following restrictions:
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//
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// 1. The origin of this software must not be misrepresented; you must not
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// claim that you wrote the original software. If you use this software
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// in a product, an acknowledgment in the product documentation would be
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// appreciated but is not required.
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// 2. Altered source versions must be plainly marked as such, and must not be
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// misrepresented as being the original software.
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// 3. This notice may not be removed or altered from any source distribution.
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#include <common.h>
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#include <malloc.h>
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#include "picopng.h"
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/*************************************************************************************************/
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typedef struct png_alloc_node {
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struct png_alloc_node *prev, *next;
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void *addr;
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size_t size;
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} png_alloc_node_t;
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png_alloc_node_t *png_alloc_head = NULL;
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png_alloc_node_t *png_alloc_tail = NULL;
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png_alloc_node_t *png_alloc_find_node(void *addr)
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{
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png_alloc_node_t *node;
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for (node = png_alloc_head; node; node = node->next)
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if (node->addr == addr)
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break;
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return node;
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}
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void png_alloc_add_node(void *addr, size_t size)
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{
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png_alloc_node_t *node;
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if (png_alloc_find_node(addr))
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return;
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node = malloc(sizeof (png_alloc_node_t));
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node->addr = addr;
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node->size = size;
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node->prev = png_alloc_tail;
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node->next = NULL;
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png_alloc_tail = node;
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if (node->prev)
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node->prev->next = node;
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if (!png_alloc_head)
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png_alloc_head = node;
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}
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void png_alloc_remove_node(png_alloc_node_t *node)
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{
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if (node->prev)
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node->prev->next = node->next;
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if (node->next)
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node->next->prev = node->prev;
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if (node == png_alloc_head)
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png_alloc_head = node->next;
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if (node == png_alloc_tail)
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png_alloc_tail = node->prev;
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node->prev = node->next = node->addr = NULL;
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free(node);
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}
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void *png_alloc_malloc(size_t size)
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{
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void *addr = malloc(size);
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png_alloc_add_node(addr, size);
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return addr;
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}
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void *png_alloc_realloc(void *addr, size_t size)
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{
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void *new_addr;
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if (!addr)
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return png_alloc_malloc(size);
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new_addr = realloc(addr, size);
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if (new_addr != addr) {
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png_alloc_node_t *old_node;
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old_node = png_alloc_find_node(addr);
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png_alloc_remove_node(old_node);
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png_alloc_add_node(new_addr, size);
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}
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return new_addr;
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}
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void png_alloc_free(void *addr)
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{
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png_alloc_node_t *node = png_alloc_find_node(addr);
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if (!node)
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return;
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png_alloc_remove_node(node);
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free(addr);
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}
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void png_alloc_free_all()
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{
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while (png_alloc_tail) {
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void *addr = png_alloc_tail->addr;
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png_alloc_remove_node(png_alloc_tail);
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free(addr);
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}
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}
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/*************************************************************************************************/
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__maybe_unused void vector32_cleanup(vector32_t *p)
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{
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p->size = p->allocsize = 0;
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if (p->data)
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png_alloc_free(p->data);
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p->data = NULL;
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}
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uint32_t vector32_resize(vector32_t *p, size_t size)
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{ // returns 1 if success, 0 if failure ==> nothing done
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if (size * sizeof (uint32_t) > p->allocsize) {
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size_t newsize = size * sizeof (uint32_t) * 2;
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void *data = png_alloc_realloc(p->data, newsize);
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if (data) {
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p->allocsize = newsize;
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p->data = (uint32_t *) data;
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p->size = size;
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} else
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return 0;
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} else
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p->size = size;
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return 1;
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}
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uint32_t vector32_resizev(vector32_t *p, size_t size, uint32_t value)
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{ // resize and give all new elements the value
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size_t oldsize = p->size, i;
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if (!vector32_resize(p, size))
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return 0;
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for (i = oldsize; i < size; i++)
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p->data[i] = value;
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return 1;
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}
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void vector32_init(vector32_t *p)
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{
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p->data = NULL;
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p->size = p->allocsize = 0;
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}
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vector32_t *vector32_new(size_t size, uint32_t value)
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{
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vector32_t *p = png_alloc_malloc(sizeof (vector32_t));
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vector32_init(p);
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if (size && !vector32_resizev(p, size, value))
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return NULL;
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return p;
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}
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/*************************************************************************************************/
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__maybe_unused void vector8_cleanup(vector8_t *p)
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{
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p->size = p->allocsize = 0;
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if (p->data)
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png_alloc_free(p->data);
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p->data = NULL;
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}
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uint32_t vector8_resize(vector8_t *p, size_t size)
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{ // returns 1 if success, 0 if failure ==> nothing done
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// xxx: the use of sizeof uint32_t here seems like a bug (this descends from the lodepng vector
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// compatibility functions which do the same). without this there is corruption in certain cases,
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// so this was probably done to cover up allocation bug(s) in the original picopng code!
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if (size * sizeof (uint32_t) > p->allocsize) {
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size_t newsize = size * sizeof (uint32_t) * 2;
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void *data = png_alloc_realloc(p->data, newsize);
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if (data) {
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p->allocsize = newsize;
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p->data = (uint8_t *) data;
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p->size = size;
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} else
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return 0; // error: not enough memory
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} else
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p->size = size;
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return 1;
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}
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uint32_t vector8_resizev(vector8_t *p, size_t size, uint8_t value)
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{ // resize and give all new elements the value
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size_t oldsize = p->size, i;
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if (!vector8_resize(p, size))
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return 0;
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for (i = oldsize; i < size; i++)
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p->data[i] = value;
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return 1;
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}
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void vector8_init(vector8_t *p)
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{
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p->data = NULL;
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p->size = p->allocsize = 0;
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}
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vector8_t *vector8_new(size_t size, uint8_t value)
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{
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vector8_t *p = png_alloc_malloc(sizeof (vector8_t));
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vector8_init(p);
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if (size && !vector8_resizev(p, size, value))
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return NULL;
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return p;
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}
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vector8_t *vector8_copy(vector8_t *p)
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{
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vector8_t *q = vector8_new(p->size, 0);
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uint32_t n;
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for (n = 0; n < q->size; n++)
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q->data[n] = p->data[n];
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return q;
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}
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/*************************************************************************************************/
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int Zlib_decompress(vector8_t *out, const vector8_t *in) // returns error value
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{
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return picopng_zlib_decompress(out->data, out->size, in->data, in->size);
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}
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/*************************************************************************************************/
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#define PNG_SIGNATURE 0x0a1a0a0d474e5089ull
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#define CHUNK_IHDR 0x52444849
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#define CHUNK_IDAT 0x54414449
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#define CHUNK_IEND 0x444e4549
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#define CHUNK_PLTE 0x45544c50
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#define CHUNK_tRNS 0x534e5274
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int PNG_error;
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uint32_t PNG_readBitFromReversedStream(size_t *bitp, const uint8_t *bits)
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{
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uint32_t result = (bits[*bitp >> 3] >> (7 - (*bitp & 0x7))) & 1;
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(*bitp)++;
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return result;
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}
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uint32_t PNG_readBitsFromReversedStream(size_t *bitp, const uint8_t *bits, uint32_t nbits)
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{
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uint32_t i, result = 0;
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for (i = nbits - 1; i < nbits; i--)
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result += ((PNG_readBitFromReversedStream(bitp, bits)) << i);
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return result;
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}
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void PNG_setBitOfReversedStream(size_t *bitp, uint8_t *bits, uint32_t bit)
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{
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bits[*bitp >> 3] |= (bit << (7 - (*bitp & 0x7)));
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(*bitp)++;
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}
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uint32_t PNG_read32bitInt(const uint8_t *buffer)
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{
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return (buffer[0] << 24) | (buffer[1] << 16) | (buffer[2] << 8) | buffer[3];
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}
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int PNG_checkColorValidity(uint32_t colorType, uint32_t bd) // return type is a LodePNG error code
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{
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if ((colorType == 2 || colorType == 4 || colorType == 6)) {
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if (!(bd == 8 || bd == 16))
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return 37;
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else
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return 0;
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} else if (colorType == 0) {
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if (!(bd == 1 || bd == 2 || bd == 4 || bd == 8 || bd == 16))
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return 37;
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else
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return 0;
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} else if (colorType == 3) {
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if (!(bd == 1 || bd == 2 || bd == 4 || bd == 8))
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return 37;
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else
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return 0;
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} else
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return 31; // nonexistent color type
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}
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uint32_t PNG_getBpp(const PNG_info_t *info)
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{
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uint32_t bitDepth, colorType;
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bitDepth = info->bitDepth;
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colorType = info->colorType;
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if (colorType == 2)
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return (3 * bitDepth);
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else if (colorType >= 4)
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return (colorType - 2) * bitDepth;
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else
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return bitDepth;
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}
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void PNG_readPngHeader(PNG_info_t *info, const uint8_t *in, size_t inlength)
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{ // read the information from the header and store it in the Info
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if (inlength < 29) {
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PNG_error = 27; // error: the data length is smaller than the length of the header
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return;
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}
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if (*(uint64_t *) in != PNG_SIGNATURE) {
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PNG_error = 28; // no PNG signature
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return;
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}
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if (*(uint32_t *) &in[12] != CHUNK_IHDR) {
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PNG_error = 29; // error: it doesn't start with a IHDR chunk!
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return;
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}
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info->width = PNG_read32bitInt(&in[16]);
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info->height = PNG_read32bitInt(&in[20]);
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info->bitDepth = in[24];
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info->colorType = in[25];
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info->compressionMethod = in[26];
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if (in[26] != 0) {
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PNG_error = 32; // error: only compression method 0 is allowed in the specification
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return;
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}
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info->filterMethod = in[27];
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if (in[27] != 0) {
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PNG_error = 33; // error: only filter method 0 is allowed in the specification
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return;
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}
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info->interlaceMethod = in[28];
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if (in[28] > 1) {
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PNG_error = 34; // error: only interlace methods 0 and 1 exist in the specification
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return;
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}
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PNG_error = PNG_checkColorValidity(info->colorType, info->bitDepth);
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}
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int PNG_paethPredictor(int a, int b, int c) // Paeth predicter, used by PNG filter type 4
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{
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int p, pa, pb, pc;
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p = a + b - c;
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pa = p > a ? (p - a) : (a - p);
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pb = p > b ? (p - b) : (b - p);
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pc = p > c ? (p - c) : (c - p);
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return (pa <= pb && pa <= pc) ? a : (pb <= pc ? b : c);
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}
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void PNG_unFilterScanline(uint8_t *recon, const uint8_t *scanline, const uint8_t *precon,
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size_t bytewidth, uint32_t filterType, size_t length)
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{
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size_t i;
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switch (filterType) {
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case 0:
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for (i = 0; i < length; i++)
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recon[i] = scanline[i];
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break;
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case 1:
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for (i = 0; i < bytewidth; i++)
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recon[i] = scanline[i];
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for (i = bytewidth; i < length; i++)
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recon[i] = scanline[i] + recon[i - bytewidth];
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break;
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case 2:
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if (precon)
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for (i = 0; i < length; i++)
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recon[i] = scanline[i] + precon[i];
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else
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for (i = 0; i < length; i++)
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recon[i] = scanline[i];
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break;
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case 3:
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if (precon) {
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for (i = 0; i < bytewidth; i++)
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recon[i] = scanline[i] + precon[i] / 2;
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for (i = bytewidth; i < length; i++)
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recon[i] = scanline[i] + ((recon[i - bytewidth] + precon[i]) / 2);
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} else {
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for (i = 0; i < bytewidth; i++)
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recon[i] = scanline[i];
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for (i = bytewidth; i < length; i++)
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recon[i] = scanline[i] + recon[i - bytewidth] / 2;
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}
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break;
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case 4:
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if (precon) {
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for (i = 0; i < bytewidth; i++)
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recon[i] = (uint8_t) (scanline[i] + PNG_paethPredictor(0, precon[i], 0));
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for (i = bytewidth; i < length; i++)
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recon[i] = (uint8_t) (scanline[i] + PNG_paethPredictor(recon[i - bytewidth],
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precon[i], precon[i - bytewidth]));
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} else {
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for (i = 0; i < bytewidth; i++)
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recon[i] = scanline[i];
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for (i = bytewidth; i < length; i++)
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recon[i] = (uint8_t) (scanline[i] + PNG_paethPredictor(recon[i - bytewidth], 0, 0));
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}
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break;
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default:
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PNG_error = 36; // error: nonexistent filter type given
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return;
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}
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}
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void PNG_adam7Pass(uint8_t *out, uint8_t *linen, uint8_t *lineo, const uint8_t *in, uint32_t w,
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size_t passleft, size_t passtop, size_t spacex, size_t spacey, size_t passw, size_t passh,
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uint32_t bpp)
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{
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size_t bytewidth, linelength;
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uint32_t y;
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uint8_t *temp;
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// filter and reposition the pixels into the output when the image is Adam7 interlaced. This
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// function can only do it after the full image is already decoded. The out buffer must have
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// the correct allocated memory size already.
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if (passw == 0)
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return;
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bytewidth = (bpp + 7) / 8;
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linelength = 1 + ((bpp * passw + 7) / 8);
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for (y = 0; y < passh; y++) {
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size_t i, b;
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uint8_t filterType = in[y * linelength], *prevline = (y == 0) ? 0 : lineo;
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PNG_unFilterScanline(linen, &in[y * linelength + 1], prevline, bytewidth, filterType,
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(w * bpp + 7) / 8);
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if (PNG_error)
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return;
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if (bpp >= 8)
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for (i = 0; i < passw; i++)
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for (b = 0; b < bytewidth; b++) // b = current byte of this pixel
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out[bytewidth * w * (passtop + spacey * y) + bytewidth *
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(passleft + spacex * i) + b] = linen[bytewidth * i + b];
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else
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for (i = 0; i < passw; i++) {
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size_t obp, bp;
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obp = bpp * w * (passtop + spacey * y) + bpp * (passleft + spacex * i);
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bp = i * bpp;
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for (b = 0; b < bpp; b++)
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PNG_setBitOfReversedStream(&obp, out, PNG_readBitFromReversedStream(&bp, linen));
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}
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temp = linen;
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linen = lineo;
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lineo = temp; // swap the two buffer pointers "line old" and "line new"
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}
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}
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int PNG_convert(const PNG_info_t *info, vector8_t *out, const uint8_t *in)
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{ // converts from any color type to 32-bit. return value = LodePNG error code
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size_t i, c;
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uint32_t bitDepth, colorType;
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size_t numpixels, bp;
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uint8_t *out_data;
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bitDepth = info->bitDepth;
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colorType = info->colorType;
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numpixels = info->width * info->height;
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bp = 0;
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vector8_resize(out, numpixels * 4);
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out_data = out->size ? out->data : 0;
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if (bitDepth == 8 && colorType == 0) // greyscale
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for (i = 0; i < numpixels; i++) {
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out_data[4 * i + 0] = out_data[4 * i + 1] = out_data[4 * i + 2] = in[i];
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out_data[4 * i + 3] = (info->key_defined && (in[i] == info->key_r)) ? 0 : 255;
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}
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else if (bitDepth == 8 && colorType == 2) // RGB color
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for (i = 0; i < numpixels; i++) {
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for (c = 0; c < 3; c++)
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out_data[4 * i + c] = in[3 * i + c];
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out_data[4 * i + 3] = (info->key_defined && (in[3 * i + 0] == info->key_r) &&
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|
(in[3 * i + 1] == info->key_g) && (in[3 * i + 2] == info->key_b)) ? 0 : 255;
|
|
}
|
|
else if (bitDepth == 8 && colorType == 3) // indexed color (palette)
|
|
for (i = 0; i < numpixels; i++) {
|
|
if (4U * in[i] >= info->palette->size)
|
|
return 46;
|
|
for (c = 0; c < 4; c++) // get rgb colors from the palette
|
|
out_data[4 * i + c] = info->palette->data[4 * in[i] + c];
|
|
}
|
|
else if (bitDepth == 8 && colorType == 4) // greyscale with alpha
|
|
for (i = 0; i < numpixels; i++) {
|
|
out_data[4 * i + 0] = out_data[4 * i + 1] = out_data[4 * i + 2] = in[2 * i + 0];
|
|
out_data[4 * i + 3] = in[2 * i + 1];
|
|
}
|
|
else if (bitDepth == 8 && colorType == 6)
|
|
for (i = 0; i < numpixels; i++)
|
|
for (c = 0; c < 4; c++)
|
|
out_data[4 * i + c] = in[4 * i + c]; // RGB with alpha
|
|
else if (bitDepth == 16 && colorType == 0) // greyscale
|
|
for (i = 0; i < numpixels; i++) {
|
|
out_data[4 * i + 0] = out_data[4 * i + 1] = out_data[4 * i + 2] = in[2 * i];
|
|
out_data[4 * i + 3] = (info->key_defined && (256U * in[i] + in[i + 1] == info->key_r))
|
|
? 0 : 255;
|
|
}
|
|
else if (bitDepth == 16 && colorType == 2) // RGB color
|
|
for (i = 0; i < numpixels; i++) {
|
|
for (c = 0; c < 3; c++)
|
|
out_data[4 * i + c] = in[6 * i + 2 * c];
|
|
out_data[4 * i + 3] = (info->key_defined &&
|
|
(256U * in[6 * i + 0] + in[6 * i + 1] == info->key_r) &&
|
|
(256U * in[6 * i + 2] + in[6 * i + 3] == info->key_g) &&
|
|
(256U * in[6 * i + 4] + in[6 * i + 5] == info->key_b)) ? 0 : 255;
|
|
}
|
|
else if (bitDepth == 16 && colorType == 4) // greyscale with alpha
|
|
for (i = 0; i < numpixels; i++) {
|
|
out_data[4 * i + 0] = out_data[4 * i + 1] = out_data[4 * i + 2] = in[4 * i]; // msb
|
|
out_data[4 * i + 3] = in[4 * i + 2];
|
|
}
|
|
else if (bitDepth == 16 && colorType == 6)
|
|
for (i = 0; i < numpixels; i++)
|
|
for (c = 0; c < 4; c++)
|
|
out_data[4 * i + c] = in[8 * i + 2 * c]; // RGB with alpha
|
|
else if (bitDepth < 8 && colorType == 0) // greyscale
|
|
for (i = 0; i < numpixels; i++) {
|
|
uint32_t value = (PNG_readBitsFromReversedStream(&bp, in, bitDepth) * 255) /
|
|
((1 << bitDepth) - 1); // scale value from 0 to 255
|
|
out_data[4 * i + 0] = out_data[4 * i + 1] = out_data[4 * i + 2] = (uint8_t) value;
|
|
out_data[4 * i + 3] = (info->key_defined && value &&
|
|
(((1U << bitDepth) - 1U) == info->key_r) && ((1U << bitDepth) - 1U)) ? 0 : 255;
|
|
}
|
|
else if (bitDepth < 8 && colorType == 3) // palette
|
|
for (i = 0; i < numpixels; i++) {
|
|
uint32_t value = PNG_readBitsFromReversedStream(&bp, in, bitDepth);
|
|
if (4 * value >= info->palette->size)
|
|
return 47;
|
|
for (c = 0; c < 4; c++) // get rgb colors from the palette
|
|
out_data[4 * i + c] = info->palette->data[4 * value + c];
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
PNG_info_t *PNG_info_new(void)
|
|
{
|
|
PNG_info_t *info = png_alloc_malloc(sizeof (PNG_info_t));
|
|
uint32_t i;
|
|
for (i = 0; i < sizeof (PNG_info_t); i++)
|
|
((uint8_t *) info)[i] = 0;
|
|
info->palette = vector8_new(0, 0);
|
|
info->image = vector8_new(0, 0);
|
|
return info;
|
|
}
|
|
|
|
PNG_info_t *PNG_decode(const uint8_t *in, uint32_t size)
|
|
{
|
|
PNG_info_t *info;
|
|
size_t pos;
|
|
vector8_t *idat;
|
|
bool IEND, known_type;
|
|
uint32_t bpp;
|
|
vector8_t *scanlines; // now the out buffer will be filled
|
|
size_t bytewidth, outlength;
|
|
uint8_t *out_data;
|
|
|
|
PNG_error = 0;
|
|
|
|
if (size == 0 || in == 0) {
|
|
PNG_error = 48; // the given data is empty
|
|
return NULL;
|
|
}
|
|
info = PNG_info_new();
|
|
PNG_readPngHeader(info, in, size);
|
|
if (PNG_error)
|
|
return NULL;
|
|
pos = 33; // first byte of the first chunk after the header
|
|
idat = NULL; // the data from idat chunks
|
|
IEND = false;
|
|
known_type = true;
|
|
info->key_defined = false;
|
|
// loop through the chunks, ignoring unknown chunks and stopping at IEND chunk. IDAT data is
|
|
// put at the start of the in buffer
|
|
while (!IEND) {
|
|
size_t i, j;
|
|
size_t chunkLength;
|
|
uint32_t chunkType;
|
|
|
|
if (pos + 8 >= size) {
|
|
PNG_error = 30; // error: size of the in buffer too small to contain next chunk
|
|
return NULL;
|
|
}
|
|
chunkLength = PNG_read32bitInt(&in[pos]);
|
|
pos += 4;
|
|
if (chunkLength > 0x7fffffff) {
|
|
PNG_error = 63;
|
|
return NULL;
|
|
}
|
|
if (pos + chunkLength >= size) {
|
|
PNG_error = 35; // error: size of the in buffer too small to contain next chunk
|
|
return NULL;
|
|
}
|
|
chunkType = *(uint32_t *) &in[pos];
|
|
if (chunkType == CHUNK_IDAT) { // IDAT: compressed image data chunk
|
|
size_t offset = 0;
|
|
if (idat) {
|
|
offset = idat->size;
|
|
vector8_resize(idat, offset + chunkLength);
|
|
} else
|
|
idat = vector8_new(chunkLength, 0);
|
|
for (i = 0; i < chunkLength; i++)
|
|
idat->data[offset + i] = in[pos + 4 + i];
|
|
pos += (4 + chunkLength);
|
|
} else if (chunkType == CHUNK_IEND) { // IEND
|
|
pos += 4;
|
|
IEND = true;
|
|
} else if (chunkType == CHUNK_PLTE) { // PLTE: palette chunk
|
|
pos += 4; // go after the 4 letters
|
|
vector8_resize(info->palette, 4 * (chunkLength / 3));
|
|
if (info->palette->size > (4 * 256)) {
|
|
PNG_error = 38; // error: palette too big
|
|
return NULL;
|
|
}
|
|
for (i = 0; i < info->palette->size; i += 4) {
|
|
for (j = 0; j < 3; j++)
|
|
info->palette->data[i + j] = in[pos++]; // RGB
|
|
info->palette->data[i + 3] = 255; // alpha
|
|
}
|
|
} else if (chunkType == CHUNK_tRNS) { // tRNS: palette transparency chunk
|
|
pos += 4; // go after the 4 letters
|
|
if (info->colorType == 3) {
|
|
if (4 * chunkLength > info->palette->size) {
|
|
PNG_error = 39; // error: more alpha values given than there are palette entries
|
|
return NULL;
|
|
}
|
|
for (i = 0; i < chunkLength; i++)
|
|
info->palette->data[4 * i + 3] = in[pos++];
|
|
} else if (info->colorType == 0) {
|
|
if (chunkLength != 2) {
|
|
PNG_error = 40; // error: this chunk must be 2 bytes for greyscale image
|
|
return NULL;
|
|
}
|
|
info->key_defined = true;
|
|
info->key_r = info->key_g = info->key_b = 256 * in[pos] + in[pos + 1];
|
|
pos += 2;
|
|
} else if (info->colorType == 2) {
|
|
if (chunkLength != 6) {
|
|
PNG_error = 41; // error: this chunk must be 6 bytes for RGB image
|
|
return NULL;
|
|
}
|
|
info->key_defined = true;
|
|
info->key_r = 256 * in[pos] + in[pos + 1];
|
|
pos += 2;
|
|
info->key_g = 256 * in[pos] + in[pos + 1];
|
|
pos += 2;
|
|
info->key_b = 256 * in[pos] + in[pos + 1];
|
|
pos += 2;
|
|
} else {
|
|
PNG_error = 42; // error: tRNS chunk not allowed for other color models
|
|
return NULL;
|
|
}
|
|
} else { // it's not an implemented chunk type, so ignore it: skip over the data
|
|
if (!(in[pos + 0] & 32)) {
|
|
// error: unknown critical chunk (5th bit of first byte of chunk type is 0)
|
|
PNG_error = 69;
|
|
return NULL;
|
|
}
|
|
pos += (chunkLength + 4); // skip 4 letters and uninterpreted data of unimplemented chunk
|
|
known_type = false;
|
|
}
|
|
pos += 4; // step over CRC (which is ignored)
|
|
}
|
|
bpp = PNG_getBpp(info);
|
|
scanlines = vector8_new(((info->width * (info->height * bpp + 7)) / 8) + info->height, 0);
|
|
PNG_error = Zlib_decompress(scanlines, idat);
|
|
if (PNG_error)
|
|
return NULL; // stop if the zlib decompressor returned an error
|
|
bytewidth = (bpp + 7) / 8;
|
|
outlength = (info->height * info->width * bpp + 7) / 8;
|
|
vector8_resize(info->image, outlength); // time to fill the out buffer
|
|
out_data = outlength ? info->image->data : 0;
|
|
if (info->interlaceMethod == 0) { // no interlace, just filter
|
|
size_t y, obp, bp;
|
|
size_t linestart, linelength;
|
|
linestart = 0;
|
|
// length in bytes of a scanline, excluding the filtertype byte
|
|
linelength = (info->width * bpp + 7) / 8;
|
|
if (bpp >= 8) // byte per byte
|
|
for (y = 0; y < info->height; y++) {
|
|
uint32_t filterType = scanlines->data[linestart];
|
|
const uint8_t *prevline;
|
|
prevline = (y == 0) ? 0 : &out_data[(y - 1) * info->width * bytewidth];
|
|
PNG_unFilterScanline(&out_data[linestart - y], &scanlines->data[linestart + 1],
|
|
prevline, bytewidth, filterType, linelength);
|
|
if (PNG_error)
|
|
return NULL;
|
|
linestart += (1 + linelength); // go to start of next scanline
|
|
} else { // less than 8 bits per pixel, so fill it up bit per bit
|
|
vector8_t *templine; // only used if bpp < 8
|
|
templine = vector8_new((info->width * bpp + 7) >> 3, 0);
|
|
for (y = 0, obp = 0; y < info->height; y++) {
|
|
uint32_t filterType = scanlines->data[linestart];
|
|
const uint8_t *prevline;
|
|
prevline = (y == 0) ? 0 : &out_data[(y - 1) * info->width * bytewidth];
|
|
PNG_unFilterScanline(templine->data, &scanlines->data[linestart + 1], prevline,
|
|
bytewidth, filterType, linelength);
|
|
if (PNG_error)
|
|
return NULL;
|
|
for (bp = 0; bp < info->width * bpp;)
|
|
PNG_setBitOfReversedStream(&obp, out_data, PNG_readBitFromReversedStream(&bp,
|
|
templine->data));
|
|
linestart += (1 + linelength); // go to start of next scanline
|
|
}
|
|
}
|
|
} else { // interlaceMethod is 1 (Adam7)
|
|
int i;
|
|
vector8_t *scanlineo, *scanlinen; // "old" and "new" scanline
|
|
size_t passw[7] = {
|
|
(info->width + 7) / 8, (info->width + 3) / 8, (info->width + 3) / 4,
|
|
(info->width + 1) / 4, (info->width + 1) / 2, (info->width + 0) / 2,
|
|
(info->width + 0) / 1
|
|
};
|
|
size_t passh[7] = {
|
|
(info->height + 7) / 8, (info->height + 7) / 8, (info->height + 3) / 8,
|
|
(info->height + 3) / 4, (info->height + 1) / 4, (info->height + 1) / 2,
|
|
(info->height + 0) / 2
|
|
};
|
|
size_t passstart[7] = { 0 };
|
|
size_t pattern[28] = { 0, 4, 0, 2, 0, 1, 0, 0, 0, 4, 0, 2, 0, 1, 8, 8, 4, 4, 2, 2, 1, 8, 8,
|
|
8, 4, 4, 2, 2 }; // values for the adam7 passes
|
|
for (i = 0; i < 6; i++)
|
|
passstart[i + 1] = passstart[i] + passh[i] * ((passw[i] ? 1 : 0) + (passw[i] * bpp + 7) / 8);
|
|
scanlineo = vector8_new((info->width * bpp + 7) / 8, 0);
|
|
scanlinen = vector8_new((info->width * bpp + 7) / 8, 0);
|
|
for (i = 0; i < 7; i++)
|
|
PNG_adam7Pass(out_data, scanlinen->data, scanlineo->data, &scanlines->data[passstart[i]],
|
|
info->width, pattern[i], pattern[i + 7], pattern[i + 14], pattern[i + 21],
|
|
passw[i], passh[i], bpp);
|
|
}
|
|
if (info->colorType != 6 || info->bitDepth != 8) { // conversion needed
|
|
vector8_t *copy = vector8_copy(info->image); // xxx: is this copy necessary?
|
|
PNG_error = PNG_convert(info, info->image, copy->data);
|
|
}
|
|
return info;
|
|
}
|
|
|
|
/*************************************************************************************************/
|
|
|
|
#ifdef TEST
|
|
|
|
#include <stdio.h>
|
|
#include <sys/stat.h>
|
|
|
|
int main(int argc, char **argv)
|
|
{
|
|
char *fname = (argc > 1) ? argv[1] : "test.png";
|
|
PNG_info_t *info;
|
|
struct stat statbuf;
|
|
uint32_t insize, outsize;
|
|
FILE *infp, *outfp;
|
|
uint8_t *inbuf;
|
|
uint32_t n;
|
|
|
|
if (stat(fname, &statbuf) != 0) {
|
|
perror("stat");
|
|
return 1;
|
|
} else if (!statbuf.st_size) {
|
|
printf("file empty\n");
|
|
return 1;
|
|
}
|
|
insize = (uint32_t) statbuf.st_size;
|
|
inbuf = malloc(insize);
|
|
infp = fopen(fname, "rb");
|
|
if (!infp) {
|
|
perror("fopen");
|
|
free(inbuf);
|
|
return 1;
|
|
} else if (fread(inbuf, 1, insize, infp) != insize) {
|
|
perror("fread");
|
|
free(inbuf);
|
|
fclose(infp);
|
|
return 1;
|
|
}
|
|
fclose(infp);
|
|
|
|
printf("input file: %s (size: %d)\n", fname, insize);
|
|
|
|
info = PNG_decode(inbuf, insize);
|
|
free(inbuf);
|
|
printf("PNG_error: %d\n", PNG_error);
|
|
if (PNG_error != 0)
|
|
return 1;
|
|
|
|
printf("width: %d, height: %d\nfirst 16 bytes: ", info->width, info->height);
|
|
for (n = 0; n < 16; n++)
|
|
printf("%02x ", info->image->data[n]);
|
|
printf("\n");
|
|
|
|
outsize = info->width * info->height * 4;
|
|
printf("image size: %d\n", outsize);
|
|
if (outsize != info->image->size) {
|
|
printf("error: image size doesn't match dimensions\n");
|
|
return 1;
|
|
}
|
|
outfp = fopen("out.bin", "wb");
|
|
if (!outfp) {
|
|
perror("fopen");
|
|
return 1;
|
|
} else if (fwrite(info->image->data, 1, outsize, outfp) != outsize) {
|
|
perror("fwrite");
|
|
fclose(outfp);
|
|
return 1;
|
|
}
|
|
fclose(outfp);
|
|
|
|
#ifdef ALLOC_DEBUG
|
|
png_alloc_node_t *node;
|
|
for (node = png_alloc_head, n = 1; node; node = node->next, n++)
|
|
printf("node %d (%p) addr = %p, size = %zu\n", n, node, node->addr, node->size);
|
|
#endif
|
|
png_alloc_free_all(); // also frees info and image data from PNG_decode
|
|
|
|
return 0;
|
|
}
|
|
|
|
#endif
|