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+/****************************************************************************
+**
+** Implementation of PNG TQImage IOHandler
+**
+** Created : 970521
+**
+** Copyright (C) 2010 Timothy Pearson and (C) 1992-2008 Trolltech ASA.
+**
+** This file is part of the kernel module of the TQt GUI Toolkit.
+**
+** This file may be used under the terms of the GNU General
+** Public License versions 2.0 or 3.0 as published by the Free
+** Software Foundation and appearing in the files LICENSE.GPL2
+** and LICENSE.GPL3 included in the packaging of this file.
+** Alternatively you may (at your option) use any later version
+** of the GNU General Public License if such license has been
+** publicly approved by Trolltech ASA (or its successors, if any)
+** and the KDE Free TQt Foundation.
+**
+** Please review the following information to ensure GNU General
+** Public Licensing requirements will be met:
+** http://trolltech.com/products/qt/licenses/licensing/opensource/.
+** If you are unsure which license is appropriate for your use, please
+** review the following information:
+** http://trolltech.com/products/qt/licenses/licensing/licensingoverview
+** or contact the sales department at sales@trolltech.com.
+**
+** This file may be used under the terms of the Q Public License as
+** defined by Trolltech ASA and appearing in the file LICENSE.TQPL
+** included in the packaging of this file. Licensees holding valid TQt
+** Commercial licenses may use this file in accordance with the TQt
+** Commercial License Agreement provided with the Software.
+**
+** This file is provided "AS IS" with NO WARRANTY OF ANY KIND,
+** INCLUDING THE WARRANTIES OF DESIGN, MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE. Trolltech reserves all rights not granted
+** herein.
+**
+**********************************************************************/
+
+#include "tqpngio.h"
+
+#ifndef TQT_NO_IMAGEIO_PNG
+
+#include "tqasyncimageio.h"
+#include "tqiodevice.h"
+
+#include <png.h>
+
+
+#ifdef TQ_OS_TEMP
+#define CALLBACK_CALL_TYPE __cdecl
+#else
+#define CALLBACK_CALL_TYPE
+#endif
+
+
+/*
+ All PNG files load to the minimal TQImage equivalent.
+
+ All TQImage formats output to reasonably efficient PNG equivalents.
+ Never to grayscale.
+*/
+
+#if defined(TQ_C_CALLBACKS)
+extern "C" {
+#endif
+
+static
+void CALLBACK_CALL_TYPE iod_read_fn(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+ TQImageIO* iio = (TQImageIO*)png_get_io_ptr(png_ptr);
+ TQIODevice* in = iio->ioDevice();
+
+ while (length) {
+ int nr = in->readBlock((char*)data, length);
+ if (nr <= 0) {
+ png_error(png_ptr, "Read Error");
+ return;
+ }
+ length -= nr;
+ }
+}
+
+
+static
+void CALLBACK_CALL_TYPE qpiw_write_fn( png_structp png_ptr, png_bytep data, png_size_t length )
+{
+ TQPNGImageWriter* qpiw = (TQPNGImageWriter*)png_get_io_ptr( png_ptr );
+ TQIODevice* out = qpiw->tqdevice();
+
+ uint nr = out->writeBlock( (char*)data, length );
+ if ( nr != length ) {
+ png_error( png_ptr, "Write Error" );
+ return;
+ }
+}
+
+
+static
+void CALLBACK_CALL_TYPE qpiw_flush_fn( png_structp png_ptr )
+{
+ TQPNGImageWriter* qpiw = (TQPNGImageWriter*)png_get_io_ptr( png_ptr );
+ TQIODevice* out = qpiw->tqdevice();
+
+ out->flush();
+}
+
+#if defined(TQ_C_CALLBACKS)
+}
+#endif
+
+static
+void setup_qt( TQImage& image, png_structp png_ptr, png_infop info_ptr, float screen_gamma=0.0 )
+{
+ if ( screen_gamma != 0.0 && png_get_valid(png_ptr, info_ptr, PNG_INFO_gAMA) ) {
+ double file_gamma;
+ png_get_gAMA(png_ptr, info_ptr, &file_gamma);
+ png_set_gamma( png_ptr, screen_gamma, file_gamma );
+ }
+
+ png_uint_32 width;
+ png_uint_32 height;
+ int bit_depth;
+ int color_type;
+ png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
+ 0, 0, 0);
+
+ if ( color_type == PNG_COLOR_TYPE_GRAY ) {
+ // Black & White or 8-bit grayscale
+ if ( bit_depth == 1 && info_ptr->channels == 1 ) {
+ png_set_invert_mono( png_ptr );
+ png_read_update_info( png_ptr, info_ptr );
+ if (!image.create( width, height, 1, 2, TQImage::BigEndian ))
+ return;
+ image.setColor( 1, tqRgb(0,0,0) );
+ image.setColor( 0, tqRgb(255,255,255) );
+ } else if (bit_depth == 16 && png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)) {
+ png_set_expand(png_ptr);
+ png_set_strip_16(png_ptr);
+ png_set_gray_to_rgb(png_ptr);
+
+ if (!image.create(width, height, 32))
+ return;
+ image.setAlphaBuffer(TRUE);
+
+ if (TQImage::systemByteOrder() == TQImage::BigEndian)
+ png_set_swap_alpha(png_ptr);
+
+ png_read_update_info(png_ptr, info_ptr);
+ } else {
+ if ( bit_depth == 16 )
+ png_set_strip_16(png_ptr);
+ else if ( bit_depth < 8 )
+ png_set_packing(png_ptr);
+ int ncols = bit_depth < 8 ? 1 << bit_depth : 256;
+ png_read_update_info(png_ptr, info_ptr);
+ if (!image.create(width, height, 8, ncols))
+ return;
+ for (int i=0; i<ncols; i++) {
+ int c = i*255/(ncols-1);
+ image.setColor( i, tqRgba(c,c,c,0xff) );
+ }
+ if ( png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS) ) {
+ const int g = info_ptr->trans_values.gray;
+ if (g < ncols) {
+ image.setAlphaBuffer(TRUE);
+ image.setColor(g, image.color(g) & TQRGB_MASK);
+ }
+ }
+ }
+ } else if ( color_type == PNG_COLOR_TYPE_PALETTE
+ && png_get_valid(png_ptr, info_ptr, PNG_INFO_PLTE)
+ && info_ptr->num_palette <= 256 )
+ {
+ // 1-bit and 8-bit color
+ if ( bit_depth != 1 )
+ png_set_packing( png_ptr );
+ png_read_update_info( png_ptr, info_ptr );
+ png_get_IHDR(png_ptr, info_ptr,
+ &width, &height, &bit_depth, &color_type, 0, 0, 0);
+ if (!image.create(width, height, bit_depth, info_ptr->num_palette,
+ TQImage::BigEndian))
+ return;
+ int i = 0;
+ if ( png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS) ) {
+ image.setAlphaBuffer( TRUE );
+ while ( i < info_ptr->num_trans ) {
+ image.setColor(i, tqRgba(
+ info_ptr->palette[i].red,
+ info_ptr->palette[i].green,
+ info_ptr->palette[i].blue,
+ info_ptr->trans[i]
+ )
+ );
+ i++;
+ }
+ }
+ while ( i < info_ptr->num_palette ) {
+ image.setColor(i, tqRgba(
+ info_ptr->palette[i].red,
+ info_ptr->palette[i].green,
+ info_ptr->palette[i].blue,
+ 0xff
+ )
+ );
+ i++;
+ }
+ } else {
+ // 32-bit
+ if ( bit_depth == 16 )
+ png_set_strip_16(png_ptr);
+
+ png_set_expand(png_ptr);
+
+ if ( color_type == PNG_COLOR_TYPE_GRAY_ALPHA )
+ png_set_gray_to_rgb(png_ptr);
+
+ if (!image.create(width, height, 32))
+ return;
+
+ // Only add filler if no alpha, or we can get 5 channel data.
+ if (!(color_type & PNG_COLOR_MASK_ALPHA)
+ && !png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)) {
+ png_set_filler(png_ptr, 0xff,
+ TQImage::systemByteOrder() == TQImage::BigEndian ?
+ PNG_FILLER_BEFORE : PNG_FILLER_AFTER);
+ // We want 4 bytes, but it isn't an alpha channel
+ } else {
+ image.setAlphaBuffer(TRUE);
+ }
+
+ if ( TQImage::systemByteOrder() == TQImage::BigEndian ) {
+ png_set_swap_alpha(png_ptr);
+ }
+
+ png_read_update_info(png_ptr, info_ptr);
+ }
+
+ // TQt==ARGB==Big(ARGB)==Little(BGRA)
+ if ( TQImage::systemByteOrder() == TQImage::LittleEndian ) {
+ png_set_bgr(png_ptr);
+ }
+}
+
+
+#if defined(TQ_C_CALLBACKS)
+extern "C" {
+#endif
+static void CALLBACK_CALL_TYPE qt_png_warning(png_structp /*png_ptr*/, png_const_charp message)
+{
+ qWarning("libpng warning: %s", message);
+}
+
+#if defined(TQ_C_CALLBACKS)
+}
+#endif
+
+
+static
+void read_png_image(TQImageIO* iio)
+{
+ png_structp png_ptr;
+ png_infop info_ptr;
+ png_infop end_info;
+ png_bytep* row_pointers;
+
+ png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,0,0,0);
+ if (!png_ptr) {
+ iio->setqStatus(-1);
+ return;
+ }
+
+ png_set_error_fn(png_ptr, 0, 0, qt_png_warning);
+
+ info_ptr = png_create_info_struct(png_ptr);
+ if (!info_ptr) {
+ png_destroy_read_struct(&png_ptr, 0, 0);
+ iio->setqStatus(-2);
+ return;
+ }
+
+ end_info = png_create_info_struct(png_ptr);
+ if (!end_info) {
+ png_destroy_read_struct(&png_ptr, &info_ptr, 0);
+ iio->setqStatus(-3);
+ return;
+ }
+
+ if (setjmp(png_ptr->jmpbuf)) {
+ png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
+ iio->setqStatus(-4);
+ return;
+ }
+
+ png_set_read_fn(png_ptr, (void*)iio, iod_read_fn);
+ png_read_info(png_ptr, info_ptr);
+
+ TQImage image;
+ setup_qt(image, png_ptr, info_ptr, iio->gamma());
+ if (image.isNull()) {
+ png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
+ iio->setqStatus(-5);
+ return;
+ }
+
+ png_uint_32 width;
+ png_uint_32 height;
+ int bit_depth;
+ int color_type;
+ png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
+ 0, 0, 0);
+
+#if 0 // Jump tables in Qt4 can't be used this way
+ uchar** jt = image.jumpTable();
+ row_pointers=new png_bytep[height];
+
+ for (uint y=0; y<height; y++) {
+ row_pointers[y]=jt[y];
+ }
+#else
+ row_pointers=new png_bytep[height];
+
+ for (uint y=0; y<height; y++) {
+ row_pointers[y]=image.scanLine(y);
+ }
+#endif
+
+ png_read_image(png_ptr, row_pointers);
+
+#if 0 // libpng takes care of this.
+png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)
+ if (image.depth()==32 && png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)) {
+ TQRgb trans = 0xFF000000 | tqRgb(
+ (info_ptr->trans_values.red << 8 >> bit_depth)&0xff,
+ (info_ptr->trans_values.green << 8 >> bit_depth)&0xff,
+ (info_ptr->trans_values.blue << 8 >> bit_depth)&0xff);
+ for (uint y=0; y<height; y++) {
+ for (uint x=0; x<info_ptr->width; x++) {
+ if (((uint**)jt)[y][x] == trans) {
+ ((uint**)jt)[y][x] &= 0x00FFFFFF;
+ } else {
+ }
+ }
+ }
+ }
+#endif
+
+ image.setDotsPerMeterX(png_get_x_pixels_per_meter(png_ptr,info_ptr));
+ image.setDotsPerMeterY(png_get_y_pixels_per_meter(png_ptr,info_ptr));
+
+#ifndef TQT_NO_IMAGE_TEXT
+ png_textp text_ptr;
+ int num_text=0;
+ png_get_text(png_ptr,info_ptr,&text_ptr,&num_text);
+ while (num_text--) {
+ image.setText(text_ptr->key,0,text_ptr->text);
+ text_ptr++;
+ }
+#endif
+
+ delete [] row_pointers;
+
+ if ( image.hasAlphaBuffer() ) {
+ // Many PNG files lie (eg. from PhotoShop). Fortunately this loop will
+ // usually be quick to find those that tell the truth.
+ TQRgb* c;
+ int n;
+ if (image.depth()==32) {
+ c = (TQRgb*)image.bits();
+ n = image.bytesPerLine() * image.height() / 4;
+ } else {
+ c = image.tqcolorTable();
+ n = image.numColors();
+ }
+ while ( n-- && tqAlpha(*c++)==0xff )
+ ;
+ if ( n<0 ) // LIAR!
+ image.setAlphaBuffer(FALSE);
+ }
+
+ iio->setImage(image);
+
+ png_read_end(png_ptr, end_info);
+ png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
+
+ iio->setqStatus(0);
+}
+
+TQPNGImageWriter::TQPNGImageWriter(TQIODevice* iod) :
+ dev(iod),
+ frames_written(0),
+ disposal(Unspecified),
+ looping(-1),
+ ms_delay(-1),
+ gamma(0.0)
+{
+}
+
+TQPNGImageWriter::~TQPNGImageWriter()
+{
+}
+
+void TQPNGImageWriter::setDisposalMethod(DisposalMethod dm)
+{
+ disposal = dm;
+}
+
+void TQPNGImageWriter::setLooping(int loops)
+{
+ looping = loops;
+}
+
+void TQPNGImageWriter::setFrameDelay(int msecs)
+{
+ ms_delay = msecs;
+}
+
+void TQPNGImageWriter::setGamma(float g)
+{
+ gamma = g;
+}
+
+
+#ifndef TQT_NO_IMAGE_TEXT
+static void set_text(const TQImage& image, png_structp png_ptr, png_infop info_ptr, bool short_not_long)
+{
+ TQValueList<TQImageTextKeyLang> keys = image.tqtextList();
+ if ( keys.count() ) {
+ png_textp text_ptr = new png_text[keys.count()];
+ int i=0;
+ for (TQValueList<TQImageTextKeyLang>::Iterator it=keys.begin();
+ it != keys.end(); ++it)
+ {
+ TQString t = image.text(*it);
+ if ( (t.length() <= 200) == short_not_long ) {
+ if ( t.length() < 40 )
+ text_ptr[i].compression = PNG_TEXT_COMPRESSION_NONE;
+ else
+ text_ptr[i].compression = PNG_TEXT_COMPRESSION_zTXt;
+ text_ptr[i].key = (png_charp)(*it).key.data();
+ text_ptr[i].text = (png_charp)t.latin1();
+ //text_ptr[i].text = qstrdup(t.latin1());
+ i++;
+ }
+ }
+ png_set_text(png_ptr, info_ptr, text_ptr, i);
+ //for (int j=0; j<i; j++)
+ //free(text_ptr[i].text);
+ delete [] text_ptr;
+ }
+}
+#endif
+
+bool TQPNGImageWriter::writeImage(const TQImage& image, int off_x, int off_y)
+{
+ return writeImage(image, -1, off_x, off_y);
+}
+
+bool TQPNGImageWriter::writeImage(const TQImage& image, int quality_in, int off_x_in, int off_y_in)
+{
+ TQPoint offset = image.offset();
+ int off_x = off_x_in + offset.x();
+ int off_y = off_y_in + offset.y();
+
+ png_structp png_ptr;
+ png_infop info_ptr;
+ png_bytep* row_pointers;
+
+ png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING,0,0,0);
+ if (!png_ptr) {
+ return FALSE;
+ }
+
+ png_set_error_fn(png_ptr, 0, 0, qt_png_warning);
+
+ info_ptr = png_create_info_struct(png_ptr);
+ if (!info_ptr) {
+ png_destroy_write_struct(&png_ptr, 0);
+ return FALSE;
+ }
+
+ if (setjmp(png_ptr->jmpbuf)) {
+ png_destroy_write_struct(&png_ptr, &info_ptr);
+ return FALSE;
+ }
+
+ int quality = quality_in;
+ if (quality >= 0) {
+ if (quality > 9) {
+#if defined(TQT_CHECK_RANGE)
+ qWarning( "PNG: Quality %d out of range", quality );
+#endif
+ quality = 9;
+ }
+ png_set_compression_level(png_ptr, quality);
+ }
+
+ if (gamma != 0.0) {
+ png_set_gAMA(png_ptr, info_ptr, 1.0/gamma);
+ }
+
+ png_set_write_fn(png_ptr, (void*)this, qpiw_write_fn, qpiw_flush_fn);
+
+ info_ptr->channels =
+ (image.depth() == 32)
+ ? (image.hasAlphaBuffer() ? 4 : 3)
+ : 1;
+
+ png_set_IHDR(png_ptr, info_ptr, image.width(), image.height(),
+ image.depth() == 1 ? 1 : 8 /* per channel */,
+ image.depth() == 32
+ ? image.hasAlphaBuffer()
+ ? PNG_COLOR_TYPE_RGB_ALPHA
+ : PNG_COLOR_TYPE_RGB
+ : PNG_COLOR_TYPE_PALETTE, 0, 0, 0);
+
+
+ //png_set_sBIT(png_ptr, info_ptr, 8);
+ info_ptr->sig_bit.red = 8;
+ info_ptr->sig_bit.green = 8;
+ info_ptr->sig_bit.blue = 8;
+
+ if (image.depth() == 1 && image.bitOrder() == TQImage::LittleEndian)
+ png_set_packswap(png_ptr);
+
+ png_colorp palette = 0;
+ png_bytep copy_trans = 0;
+ if (image.numColors()) {
+ // Paletted
+ int num_palette = image.numColors();
+ palette = new png_color[num_palette];
+ png_set_PLTE(png_ptr, info_ptr, palette, num_palette);
+ int* trans = new int[num_palette];
+ int num_trans = 0;
+ for (int i=0; i<num_palette; i++) {
+ TQRgb rgb=image.color(i);
+ info_ptr->palette[i].red = tqRed(rgb);
+ info_ptr->palette[i].green = tqGreen(rgb);
+ info_ptr->palette[i].blue = tqBlue(rgb);
+ if (image.hasAlphaBuffer()) {
+ trans[i] = rgb >> 24;
+ if (trans[i] < 255) {
+ num_trans = i+1;
+ }
+ }
+ }
+ if (num_trans) {
+ copy_trans = new png_byte[num_trans];
+ for (int i=0; i<num_trans; i++)
+ copy_trans[i] = trans[i];
+ png_set_tRNS(png_ptr, info_ptr, copy_trans, num_trans, 0);
+ }
+ delete [] trans;
+ }
+
+ if ( image.hasAlphaBuffer() ) {
+ info_ptr->sig_bit.alpha = 8;
+ }
+
+ // Swap ARGB to RGBA (normal PNG format) before saving on
+ // BigEndian machines
+ if ( TQImage::systemByteOrder() == TQImage::BigEndian ) {
+ png_set_swap_alpha(png_ptr);
+ }
+
+ // TQt==ARGB==Big(ARGB)==Little(BGRA)
+ if ( TQImage::systemByteOrder() == TQImage::LittleEndian ) {
+ png_set_bgr(png_ptr);
+ }
+
+ if (off_x || off_y) {
+ png_set_oFFs(png_ptr, info_ptr, off_x, off_y, PNG_OFFSET_PIXEL);
+ }
+
+ if ( frames_written > 0 )
+ png_set_sig_bytes(png_ptr, 8);
+
+ if ( image.dotsPerMeterX() > 0 || image.dotsPerMeterY() > 0 ) {
+ png_set_pHYs(png_ptr, info_ptr,
+ image.dotsPerMeterX(), image.dotsPerMeterY(),
+ PNG_RESOLUTION_METER);
+ }
+
+#ifndef TQT_NO_IMAGE_TEXT
+ // Write short texts early.
+ set_text(image,png_ptr,info_ptr,TRUE);
+#endif
+
+ png_write_info(png_ptr, info_ptr);
+
+#ifndef TQT_NO_IMAGE_TEXT
+ // Write long texts later.
+ set_text(image,png_ptr,info_ptr,FALSE);
+#endif
+
+ if ( image.depth() != 1 )
+ png_set_packing(png_ptr);
+
+ if ( image.depth() == 32 && !image.hasAlphaBuffer() )
+ png_set_filler(png_ptr, 0,
+ TQImage::systemByteOrder() == TQImage::BigEndian ?
+ PNG_FILLER_BEFORE : PNG_FILLER_AFTER);
+
+ if ( looping >= 0 && frames_written == 0 ) {
+ uchar data[13] = "NETSCAPE2.0";
+ // 0123456789aBC
+ data[0xB] = looping%0x100;
+ data[0xC] = looping/0x100;
+ png_write_chunk(png_ptr, (png_byte*)"gIFx", data, 13);
+ }
+ if ( ms_delay >= 0 || disposal!=Unspecified ) {
+ uchar data[4];
+ data[0] = disposal;
+ data[1] = 0;
+ data[2] = (ms_delay/10)/0x100; // hundredths
+ data[3] = (ms_delay/10)%0x100;
+ png_write_chunk(png_ptr, (png_byte*)"gIFg", data, 4);
+ }
+
+ png_uint_32 width;
+ png_uint_32 height;
+ int bit_depth;
+ int color_type;
+ png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
+ 0, 0, 0);
+
+ uchar** jt = const_cast<TQImage*>(&image)->jumpTable();
+ row_pointers=new png_bytep[height];
+ uint y;
+ for (y=0; y<height; y++) {
+ row_pointers[y]=jt[y];
+ }
+ png_write_image(png_ptr, row_pointers);
+ delete [] row_pointers;
+
+ png_write_end(png_ptr, info_ptr);
+ frames_written++;
+
+ if ( palette )
+ delete [] palette;
+ if ( copy_trans )
+ delete [] copy_trans;
+
+ png_destroy_write_struct(&png_ptr, &info_ptr);
+
+ return TRUE;
+}
+
+static
+void write_png_image(TQImageIO* iio)
+{
+ TQPNGImageWriter writer(iio->ioDevice());
+ int quality = iio->quality();
+ if ( quality >= 0 ) {
+ quality = TQMIN( quality, 100 );
+ quality = (100-quality) * 9 / 91; // map [0,100] -> [9,0]
+ }
+ writer.setGamma(iio->gamma());
+ bool ok = writer.writeImage( iio->image(), quality );
+ iio->setqStatus( ok ? 0 : -1 );
+}
+
+/*!
+ \class TQPNGImagePacker tqpngio.h
+ \brief The TQPNGImagePacker class creates well-compressed PNG animations.
+
+ \ingroup images
+ \ingroup graphics
+
+ By using transparency, TQPNGImagePacker allows you to build a PNG
+ image from a sequence of TQImages.
+
+ Images are added using packImage().
+*/
+
+
+/*!
+ Creates an image packer that writes PNG data to IO tqdevice \a iod
+ using a \a storage_depth bit encoding (use 8 or 32, depending on
+ the desired quality and compression requirements).
+
+ If the image needs to be modified to fit in a lower-resolution
+ result (e.g. converting from 32-bit to 8-bit), use the \a
+ conversionflags to specify how you'd prefer this to happen.
+
+ \sa TQt::ImageConversionFlags
+*/
+TQPNGImagePacker::TQPNGImagePacker(TQIODevice* iod, int storage_depth,
+ int conversionflags) :
+ TQPNGImageWriter(iod),
+ depth(storage_depth),
+ convflags(conversionflags),
+ alignx(1)
+{
+}
+
+/*!
+ Aligns pixel differences to \a x pixels. For example, using 8 can
+ improve playback on certain hardware. Normally the default of
+ 1-pixel tqalignment (i.e. no tqalignment) gives better compression and
+ performance.
+*/
+void TQPNGImagePacker::setPixelAlignment(int x)
+{
+ alignx = x;
+}
+
+/*!
+ Adds the image \a img to the PNG animation, analyzing the
+ differences between this and the previous image to improve
+ compression.
+*/
+bool TQPNGImagePacker::packImage(const TQImage& img)
+{
+ TQImage image = img.convertDepth(32);
+ if ( previous.isNull() ) {
+ // First image
+ writeImage(image.convertDepth(depth,(Qt::ImageConversionFlag)convflags));
+ } else {
+ bool done;
+ int minx, maxx, miny, maxy;
+ int w = image.width();
+ int h = image.height();
+
+ TQRgb** jt = (TQRgb**)image.jumpTable();
+ TQRgb** pjt = (TQRgb**)previous.jumpTable();
+
+ // Find left edge of change
+ done = FALSE;
+ for (minx = 0; minx < w && !done; minx++) {
+ for (int ty = 0; ty < h; ty++) {
+ if ( jt[ty][minx] != pjt[ty][minx] ) {
+ done = TRUE;
+ break;
+ }
+ }
+ }
+ minx--;
+
+ // Find right edge of change
+ done = FALSE;
+ for (maxx = w-1; maxx >= 0 && !done; maxx--) {
+ for (int ty = 0; ty < h; ty++) {
+ if ( jt[ty][maxx] != pjt[ty][maxx] ) {
+ done = TRUE;
+ break;
+ }
+ }
+ }
+ maxx++;
+
+ // Find top edge of change
+ done = FALSE;
+ for (miny = 0; miny < h && !done; miny++) {
+ for (int tx = 0; tx < w; tx++) {
+ if ( jt[miny][tx] != pjt[miny][tx] ) {
+ done = TRUE;
+ break;
+ }
+ }
+ }
+ miny--;
+
+ // Find right edge of change
+ done = FALSE;
+ for (maxy = h-1; maxy >= 0 && !done; maxy--) {
+ for (int tx = 0; tx < w; tx++) {
+ if ( jt[maxy][tx] != pjt[maxy][tx] ) {
+ done = TRUE;
+ break;
+ }
+ }
+ }
+ maxy++;
+
+ if ( minx > maxx ) minx=maxx=0;
+ if ( miny > maxy ) miny=maxy=0;
+
+ if ( alignx > 1 ) {
+ minx -= minx % alignx;
+ maxx = maxx - maxx % alignx + alignx - 1;
+ }
+
+ int dw = maxx-minx+1;
+ int dh = maxy-miny+1;
+
+ TQImage diff(dw, dh, 32);
+
+ diff.setAlphaBuffer(TRUE);
+ int x, y;
+ if ( alignx < 1 )
+ alignx = 1;
+ for (y = 0; y < dh; y++) {
+ TQRgb* li = (TQRgb*)image.scanLine(y+miny)+minx;
+ TQRgb* lp = (TQRgb*)previous.scanLine(y+miny)+minx;
+ TQRgb* ld = (TQRgb*)diff.scanLine(y);
+ if ( alignx ) {
+ for (x = 0; x < dw; x+=alignx) {
+ int i;
+ for (i=0; i<alignx; i++) {
+ if ( li[x+i] != lp[x+i] )
+ break;
+ }
+ if ( i == alignx ) {
+ // All the same
+ for (i=0; i<alignx; i++) {
+ ld[x+i] = tqRgba(0,0,0,0);
+ }
+ } else {
+ // Some different
+ for (i=0; i<alignx; i++) {
+ ld[x+i] = 0xff000000 | li[x+i];
+ }
+ }
+ }
+ } else {
+ for (x = 0; x < dw; x++) {
+ if ( li[x] != lp[x] )
+ ld[x] = 0xff000000 | li[x];
+ else
+ ld[x] = tqRgba(0,0,0,0);
+ }
+ }
+ }
+
+ diff = diff.convertDepth(depth,(Qt::ImageConversionFlag)convflags);
+ if ( !writeImage(diff, minx, miny) )
+ return FALSE;
+ }
+ previous = image;
+ return TRUE;
+}
+
+
+#ifndef TQT_NO_ASYNC_IMAGE_IO
+
+class TQPNGFormat : public TQImageFormat {
+public:
+ TQPNGFormat();
+ virtual ~TQPNGFormat();
+
+ int decode(TQImage& img, TQImageConsumer* consumer,
+ const uchar* buffer, int length);
+
+ void info(png_structp png_ptr, png_infop info);
+ void row(png_structp png_ptr, png_bytep new_row,
+ png_uint_32 row_num, int pass);
+ void end(png_structp png_ptr, png_infop info);
+#ifdef PNG_USER_CHUNKS_SUPPORTED
+ int user_chunk(png_structp png_ptr,
+ png_bytep data, png_uint_32 length);
+#endif
+
+private:
+ // Animation-level information
+ enum { MovieStart, FrameStart, Inside, End } state;
+ int first_frame;
+ int base_offx;
+ int base_offy;
+
+ // Image-level information
+ png_structp png_ptr;
+ png_infop info_ptr;
+
+ // Temporary locals during single data-chunk processing
+ TQImageConsumer* consumer;
+ TQImage* image;
+ int unused_data;
+};
+
+class TQPNGFormatType : public TQImageFormatType
+{
+ TQImageFormat* decoderFor(const uchar* buffer, int length);
+ const char* formatName() const;
+};
+
+
+/*
+ \class TQPNGFormat tqpngio.h
+ \brief The TQPNGFormat class provides an incremental image decoder for PNG
+ image format.
+
+ \ingroup images
+ \ingroup graphics
+
+ This subclass of TQImageFormat decodes PNG format images,
+ including animated PNGs.
+
+ Animated PNG images are standard PNG images. The PNG standard
+ defines two extension chunks that are useful for animations:
+
+ \list
+ \i gIFg - GIF-like Graphic Control Extension.
+ This includes frame disposal, user input flag (we ignore this),
+ and inter-frame delay.
+ \i gIFx - GIF-like Application Extension.
+ This is multi-purpose, but we just use the Netscape extension
+ which specifies looping.
+ \endlist
+
+ The subimages usually contain a offset chunk (oFFs) but need not.
+
+ The first image defines the "screen" size. Any subsequent image that
+ doesn't fit is clipped.
+*/
+/* ###TODO: decide on this point. gIFg gives disposal types, so it can be done.
+ All images paste (\e not composite, just place all-channel copying)
+ over the previous image to produce a subsequent frame.
+*/
+
+/*
+ \class TQPNGFormatType tqasyncimageio.h
+ \brief The TQPNGFormatType class provides an incremental image decoder
+ for PNG image format.
+
+ \ingroup images
+ \ingroup graphics
+ \ingroup io
+
+ This subclass of TQImageFormatType recognizes PNG format images, creating
+ a TQPNGFormat when required. An instance of this class is created
+ automatically before any other factories, so you should have no need for
+ such objects.
+*/
+
+TQImageFormat* TQPNGFormatType::decoderFor(
+ const uchar* buffer, int length)
+{
+ if (length < 8) return 0;
+ if (buffer[0]==137
+ && buffer[1]=='P'
+ && buffer[2]=='N'
+ && buffer[3]=='G'
+ && buffer[4]==13
+ && buffer[5]==10
+ && buffer[6]==26
+ && buffer[7]==10)
+ return new TQPNGFormat;
+ return 0;
+}
+
+const char* TQPNGFormatType::formatName() const
+{
+ return "PNG";
+}
+
+#if defined(TQ_C_CALLBACKS)
+extern "C" {
+#endif
+
+static void
+CALLBACK_CALL_TYPE info_callback(png_structp png_ptr, png_infop info)
+{
+ TQPNGFormat* that = (TQPNGFormat*)png_get_progressive_ptr(png_ptr);
+ that->info(png_ptr,info);
+}
+
+static void
+CALLBACK_CALL_TYPE row_callback(png_structp png_ptr, png_bytep new_row,
+ png_uint_32 row_num, int pass)
+{
+ TQPNGFormat* that = (TQPNGFormat*)png_get_progressive_ptr(png_ptr);
+ that->row(png_ptr,new_row,row_num,pass);
+}
+
+static void
+CALLBACK_CALL_TYPE end_callback(png_structp png_ptr, png_infop info)
+{
+ TQPNGFormat* that = (TQPNGFormat*)png_get_progressive_ptr(png_ptr);
+ that->end(png_ptr,info);
+}
+
+#if 0
+#ifdef PNG_USER_CHUNKS_SUPPORTED
+static int
+CALLBACK_CALL_TYPE user_chunk_callback(png_structp png_ptr,
+ png_unknown_chunkp chunk)
+{
+ TQPNGFormat* that = (TQPNGFormat*)png_get_progressive_ptr(png_ptr);
+ return that->user_chunk(png_ptr,chunk->data,chunk->size);
+}
+#endif
+#endif
+
+#if defined(TQ_C_CALLBACKS)
+}
+#endif
+
+
+/*!
+ Constructs a TQPNGFormat object.
+*/
+TQPNGFormat::TQPNGFormat()
+{
+ state = MovieStart;
+ first_frame = 1;
+ base_offx = 0;
+ base_offy = 0;
+ png_ptr = 0;
+ info_ptr = 0;
+}
+
+
+/*!
+ Destroys a TQPNGFormat object.
+*/
+TQPNGFormat::~TQPNGFormat()
+{
+ if ( png_ptr )
+ png_destroy_read_struct(&png_ptr, &info_ptr, 0);
+}
+
+
+/*!
+ This function decodes some data into image changes.
+
+ Returns the number of bytes consumed.
+*/
+int TQPNGFormat::decode(TQImage& img, TQImageConsumer* cons,
+ const uchar* buffer, int length)
+{
+ consumer = cons;
+ image = &img;
+
+ if ( state != Inside ) {
+ png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, 0, 0, 0);
+ if (!png_ptr) {
+ info_ptr = 0;
+ image = 0;
+ return -1;
+ }
+
+ png_set_error_fn(png_ptr, 0, 0, qt_png_warning);
+ png_set_compression_level(png_ptr, 9);
+
+ info_ptr = png_create_info_struct(png_ptr);
+ if (!info_ptr) {
+ png_destroy_read_struct(&png_ptr, &info_ptr, 0);
+ image = 0;
+ return -1;
+ }
+
+ if (setjmp((png_ptr)->jmpbuf)) {
+ png_destroy_read_struct(&png_ptr, &info_ptr, 0);
+ image = 0;
+ return -1;
+ }
+
+ png_set_progressive_read_fn(png_ptr, (void *)this,
+ info_callback, row_callback, end_callback);
+
+#ifdef PNG_USER_CHUNKS_SUPPORTED
+ // Can't do this yet. libpng has a crash bug with unknown (user) chunks.
+ // Warwick has sent them a patch.
+ // png_set_read_user_chunk_fn(png_ptr, 0, user_chunk_callback);
+ // png_set_keep_unknown_chunks(png_ptr, 2/*HANDLE_CHUNK_IF_SAFE*/, 0, 0);
+#endif
+
+ if ( state != MovieStart && *buffer != 0211 ) {
+ // Good, no signature - the preferred way to concat PNG images.
+ // Skip them.
+ png_set_sig_bytes(png_ptr, 8);
+ }
+
+ state = Inside;
+ }
+
+ if ( !png_ptr ) return 0;
+
+ if (setjmp(png_ptr->jmpbuf)) {
+ png_destroy_read_struct(&png_ptr, &info_ptr, 0);
+ image = 0;
+ state = MovieStart;
+ return -1;
+ }
+ unused_data = 0;
+ png_process_data(png_ptr, info_ptr, (png_bytep)buffer, length);
+ int l = length - unused_data;
+
+ // TODO: send incremental stuff to consumer (optional)
+
+ if ( state != Inside ) {
+ if ( png_ptr )
+ png_destroy_read_struct(&png_ptr, &info_ptr, 0);
+ }
+
+ image = 0;
+ return l;
+}
+
+void TQPNGFormat::info(png_structp png, png_infop)
+{
+ png_set_interlace_handling(png);
+ setup_qt(*image, png, info_ptr);
+}
+
+void TQPNGFormat::row(png_structp png, png_bytep new_row,
+ png_uint_32 row_num, int)
+{
+ uchar* old_row = image->scanLine(row_num);
+ png_progressive_combine_row(png, old_row, new_row);
+}
+
+
+void TQPNGFormat::end(png_structp png, png_infop info)
+{
+ int offx = png_get_x_offset_pixels(png,info) - base_offx;
+ int offy = png_get_y_offset_pixels(png,info) - base_offy;
+ if ( first_frame ) {
+ base_offx = offx;
+ base_offy = offy;
+ first_frame = 0;
+ }
+ image->setOffset(TQPoint(offx,offy));
+ image->setDotsPerMeterX(png_get_x_pixels_per_meter(png,info));
+ image->setDotsPerMeterY(png_get_y_pixels_per_meter(png,info));
+#ifndef TQT_NO_IMAGE_TEXT
+ png_textp text_ptr;
+ int num_text=0;
+ png_get_text(png,info,&text_ptr,&num_text);
+ while (num_text--) {
+ image->setText(text_ptr->key,0,text_ptr->text);
+ text_ptr++;
+ }
+#endif
+ TQRect r(0,0,image->width(),image->height());
+ consumer->frameDone(TQPoint(offx,offy),r);
+ consumer->end();
+ state = FrameStart;
+ unused_data = (int)png->buffer_size; // Since libpng doesn't tell us
+}
+
+#ifdef PNG_USER_CHUNKS_SUPPORTED
+
+/*
+#ifndef TQT_NO_IMAGE_TEXT
+static bool skip(png_uint_32& max, png_bytep& data)
+{
+ while (*data) {
+ if ( !max ) return FALSE;
+ max--;
+ data++;
+ }
+ if ( !max ) return FALSE;
+ max--;
+ data++; // skip to after NUL
+ return TRUE;
+}
+#endif
+*/
+
+int TQPNGFormat::user_chunk(png_structp png,
+ png_bytep data, png_uint_32 length)
+{
+#if 0 // NOT SUPPORTED: experimental PNG animation.
+ // qDebug("Got %ld-byte %s chunk", length, png->chunk_name);
+ if ( 0==qstrcmp((char*)png->chunk_name, "gIFg")
+ && length == 4 ) {
+
+ //TQPNGImageWriter::DisposalMethod disposal =
+ // (TQPNGImageWriter::DisposalMethod)data[0];
+ // ### TODO: use the disposal method
+ int ms_delay = ((data[2] << 8) | data[3])*10;
+ consumer->setFramePeriod(ms_delay);
+ return 1;
+ } else if ( 0==qstrcmp((char*)png->chunk_name, "gIFx")
+ && length == 13 ) {
+ if ( tqstrncmp((char*)data,"NETSCAPE2.0",11)==0 ) {
+ int looping = (data[0xC]<<8)|data[0xB];
+ consumer->setLooping(looping);
+ return 1;
+ }
+ }
+#else
+ TQ_UNUSED( png )
+ TQ_UNUSED( data )
+ TQ_UNUSED( length )
+#endif
+
+#ifndef TQT_NO_IMAGE_TEXT
+ /*
+
+ libpng now supports this chunk.
+
+
+ if ( 0==qstrcmp((char*)png->chunk_name, "iTXt") && length>=6 ) {
+ const char* keyword = (const char*)data;
+ if ( !skip(length,data) ) return 0;
+ if ( length >= 4 ) {
+ char compression_flag = *data++;
+ char compression_method = *data++;
+ if ( compression_flag == compression_method ) {
+ // fool the compiler into thinking they're used
+ }
+ const char* lang = (const char*)data;
+ if ( !skip(length,data) ) return 0;
+ // const char* keyword_utf8 = (const char*)data;
+ if ( !skip(length,data) ) return 0;
+ const char* text_utf8 = (const char*)data;
+ if ( !skip(length,data) ) return 0;
+ TQString text = TQString::fromUtf8(text_utf8);
+ image->setText(keyword,lang[0] ? lang : 0,text);
+ return 1;
+ }
+ }
+ */
+#endif
+
+ return 0;
+}
+#endif
+
+
+static TQPNGFormatType* globalPngFormatTypeObject = 0;
+
+#endif // TQT_NO_ASYNC_IMAGE_IO
+
+static bool done = FALSE;
+void qCleanupPngIO()
+{
+#ifndef TQT_NO_ASYNC_IMAGE_IO
+ if ( globalPngFormatTypeObject ) {
+ delete globalPngFormatTypeObject;
+ globalPngFormatTypeObject = 0;
+ }
+#endif
+ done = FALSE;
+}
+
+void qInitPngIO()
+{
+ if ( !done ) {
+ done = TRUE;
+ TQImageIO::defineIOHandler( "PNG", "^.PNG\r", 0, read_png_image,
+ write_png_image);
+#ifndef TQT_NO_ASYNC_IMAGE_IO
+ globalPngFormatTypeObject = new TQPNGFormatType;
+#endif
+ qAddPostRoutine( qCleanupPngIO );
+ }
+}
+
+void qt_zlib_compression_hack()
+{
+ compress(0,0,0,0);
+ uncompress(0,0,0,0);
+}
+
+#endif // TQT_NO_IMAGEIO_PNG