Aegisub/prs/png_wrap.cpp
2006-04-01 11:45:38 +00:00

143 lines
4 KiB
C++

// Copyright (c) 2006, Rodrigo Braz Monteiro
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// * Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation
// and/or other materials provided with the distribution.
// * Neither the name of the Aegisub Group nor the names of its contributors
// may be used to endorse or promote products derived from this software
// without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//
// -----------------------------------------------------------------------------
//
// AEGISUB
//
// Website: http://aegisub.cellosoft.com
// Contact: mailto:zeratul@cellosoft.com
//
///////////
// Headers
#include <png.h>
#include "png_wrap.h"
#include "prs_video_frame.h"
///////////////
// Constructor
PNGWrapper::PNGWrapper() {
initialized = false;
pos = 0;
}
//////////////
// Destructor
PNGWrapper::~PNGWrapper() {
if (initialized) End();
}
//////////////
// Read image
void PNGWrapper::Read(PRSVideoFrame *frame) {
// Begin
Begin();
// Initialize libpng structures
png_structp png_ptr = png_create_read_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (!png_ptr) throw 1;
png_infop info_ptr = png_create_info_struct(png_ptr);
if (!info_ptr) {
png_destroy_read_struct(&png_ptr, (png_infopp)NULL, (png_infopp)NULL);
throw 1;
}
png_infop end_info = png_create_info_struct(png_ptr);
if (!end_info) {
png_destroy_read_struct(&png_ptr, &info_ptr, (png_infopp)NULL);
throw 1;
}
// Set jump for error handling (man, I hate this lib)
if (setjmp(png_jmpbuf(png_ptr))) {
png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
throw 1;
}
// Set data reading
png_set_read_fn(png_ptr,this,memory_read_data);
// Read data
png_read_png(png_ptr, info_ptr, PNG_TRANSFORM_IDENTITY, NULL);
png_bytepp row_pointers = png_get_rows(png_ptr, info_ptr);
// Get image size
int w = png_get_image_width(png_ptr,info_ptr);
int h = png_get_image_height(png_ptr,info_ptr);
// Allocate frame data
int bpp = 4;
frame->ownData = true;
frame->data[0] = new char[w*h*bpp];
frame->w = w;
frame->h = h;
frame->pitch = w;
frame->colorSpace = ColorSpace_RGB32;
// Copy data to frame
char *dst = frame->data[0];
for (int i=0;i<h;i++) memcpy(dst+i*w*bpp,row_pointers[i],w*bpp);
// Clean up
png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
End();
}
//////////////
// Initialize
void PNGWrapper::Begin() {
// Check initialization
if (initialized) End();
initialized = true;
}
////////////
// Clean up
void PNGWrapper::End() {
// Check initialization
if (!initialized) return;
initialized = false;
}
/////////////
// Read data
void PNGWrapper::memory_read_data(png_structp png_ptr, png_bytep dstData, png_size_t length) {
PNGWrapper *wrapper = (PNGWrapper*) png_get_io_ptr(png_ptr);
wrapper->ReadData(dstData,length);
}
void PNGWrapper::ReadData(png_bytep dstData, png_size_t length) {
memcpy(dstData,((char*)data)+pos,length);
pos += (int) length;
}