2 * Copyright (c) 2017 Samsung Electronics Co., Ltd.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
18 #include <dali/internal/imaging/common/loader-png.h>
25 #include <dali/integration-api/debug.h>
26 #include <dali/public-api/images/image.h>
27 #include <dali/internal/legacy/tizen/platform-capabilities.h>
28 #include <dali/devel-api/adaptor-framework/pixel-buffer.h>
30 #include <dali/internal/system/common/file-closer.h>
32 using namespace Dali::Internal::Platform;
36 namespace TizenPlatform
42 // simple class to enforce clean-up of PNG structures
45 auto_png(png_structp& _png, png_infop& _info)
55 png_destroy_read_struct(&png, &info, NULL);
61 }; // struct auto_png;
63 bool LoadPngHeader(FILE *fp, unsigned int &width, unsigned int &height, png_structp &png, png_infop &info)
65 png_byte header[8] = { 0 };
67 // Check header to see if it is a PNG file
68 size_t size = InternalFile::fread(header, 1, 8, fp);
74 if(png_sig_cmp(header, 0, 8))
79 png = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
83 DALI_LOG_WARNING("Can't create PNG read structure\n");
87 info = png_create_info_struct(png);
90 DALI_LOG_WARNING("png_create_info_struct failed\n");
96 if(setjmp(png_jmpbuf(png)))
98 DALI_LOG_WARNING("error during png_init_io\n");
102 png_init_io(png, fp);
103 png_set_sig_bytes(png, 8);
106 png_read_info(png, info);
109 width = png_get_image_width(png, info);
110 height = png_get_image_height(png, info);
115 } // namespace - anonymous
117 bool LoadPngHeader( const Dali::ImageLoader::Input& input, unsigned int& width, unsigned int& height )
119 png_structp png = NULL;
120 png_infop info = NULL;
121 auto_png autoPng(png, info);
123 bool success = LoadPngHeader( input.file, width, height, png, info );
128 bool LoadBitmapFromPng( const Dali::ImageLoader::Input& input, Dali::Devel::PixelBuffer& bitmap )
130 png_structp png = NULL;
131 png_infop info = NULL;
132 auto_png autoPng(png, info);
134 /// @todo: consider parameters
136 unsigned int width, height;
138 unsigned int bpp = 0; // bytes per pixel
141 // Load info from the header
142 if( !LoadPngHeader( input.file, width, height, png, info ) )
147 Pixel::Format pixelFormat = Pixel::RGBA8888;
149 // decide pixel format
150 unsigned int colordepth = png_get_bit_depth(png, info);
152 // Ask PNGLib to convert high precision images into something we can use:
153 if (colordepth == 16)
155 png_set_strip_16(png);
159 png_byte colortype = png_get_color_type(png, info);
161 if( colortype == PNG_COLOR_TYPE_GRAY ||
162 colortype == PNG_COLOR_TYPE_GRAY_ALPHA )
164 if( colortype == PNG_COLOR_TYPE_GRAY )
166 pixelFormat = Pixel::L8;
167 if( png_get_valid(png, info, PNG_INFO_tRNS) )
169 colortype = PNG_COLOR_TYPE_GRAY_ALPHA;
170 /* expand transparency entry -> alpha channel if present */
171 png_set_tRNS_to_alpha(png);
172 pixelFormat = Pixel::LA88;
177 pixelFormat = Pixel::LA88;
182 /* expand gray (w/reduced bits) -> 8-bit RGB if necessary */
183 png_set_expand_gray_1_2_4_to_8(png);
184 /* pack all pixels to byte boundaries */
185 png_set_packing(png);
189 else if(colortype == PNG_COLOR_TYPE_RGB )
195 pixelFormat = Pixel::RGB888;
199 case 5: /// @todo is this correct for RGB16 5-6-5 ?
201 pixelFormat = Pixel::RGB565;
211 else if(colortype == PNG_COLOR_TYPE_RGBA)
217 pixelFormat = Pixel::RGBA8888;
227 else if(colortype == PNG_COLOR_TYPE_PALETTE)
233 pixelFormat = Pixel::LA88;
242 /* Expand paletted or RGB images with transparency to full alpha channels
243 * so the data will be available as RGBA quartets. PNG_INFO_tRNS = 0x10
245 if(png_get_valid(png, info, PNG_INFO_tRNS) == 0x10)
247 pixelFormat = Pixel::RGBA8888;
252 pixelFormat = Pixel::RGB888;
253 png_set_packing(png);
254 png_set_packswap(png);
255 png_set_palette_to_rgb(png);
269 DALI_LOG_WARNING( "Unsupported png format\n" );
274 bpp = Pixel::GetBytesPerPixel(pixelFormat);
276 png_read_update_info(png, info);
278 if(setjmp(png_jmpbuf(png)))
280 DALI_LOG_WARNING("error during png_read_image\n");
284 unsigned int rowBytes = png_get_rowbytes(png, info);
286 unsigned int bufferWidth = GetTextureDimension(width);
287 unsigned int bufferHeight = GetTextureDimension(height);
288 unsigned int stride = bufferWidth*bpp;
290 // not sure if this ever happens
291 if( rowBytes > stride )
293 stride = GetTextureDimension(rowBytes);
295 bpp = stride / bufferWidth;
299 pixelFormat = Pixel::RGB888;
302 pixelFormat = Pixel::RGBA8888;
310 // decode the whole image into bitmap buffer
311 auto pixels = (bitmap = Dali::Devel::PixelBuffer::New(bufferWidth, bufferHeight, pixelFormat)).GetBuffer();
313 DALI_ASSERT_DEBUG(pixels);
314 rows = reinterpret_cast< png_bytep* >( malloc(sizeof(png_bytep) * height) );
315 for(y=0; y<height; y++)
317 rows[y] = pixels + y * stride;
321 png_read_image(png, rows);
328 // simple class to enforce clean-up of PNG structures
331 AutoPngWrite(png_structp& _png, png_infop& _info)
341 png_destroy_write_struct(&png, &info);
347 }; // struct AutoPngWrite;
351 // Custom libpng write callbacks that buffer to a vector instead of a file:
354 * extern "C" linkage is used because this is a callback that we pass to a C
355 * library which is part of the underlying platform and so potentially compiled
356 * as C rather than C++.
357 * @see http://stackoverflow.com/a/2594222
359 extern "C" void WriteData(png_structp png_ptr, png_bytep data, png_size_t length)
361 DALI_ASSERT_DEBUG(png_ptr && data);
362 if(!png_ptr || !data)
366 // Make sure we don't try to propagate a C++ exception up the call stack of a pure C library:
369 // Recover our buffer for writing into:
370 Vector<unsigned char>* const encoded_img = static_cast< Vector<unsigned char>* >( png_get_io_ptr(png_ptr) );
373 const Vector<unsigned char>::SizeType bufferSize = encoded_img->Count();
374 encoded_img->Resize( bufferSize + length ); //< Can throw OOM.
375 unsigned char* const bufferBack = encoded_img->Begin() + bufferSize;
376 memcpy(bufferBack, data, length);
380 DALI_LOG_ERROR("PNG buffer for write to memory was passed from libpng as null.\n");
385 DALI_LOG_ERROR("C++ Exception caught\n");
389 /** Override the flush with a NOP to prevent libpng trying cstdlib file io. */
390 extern "C" void FlushData(png_structp png_ptr)
393 Debug::LogMessage(Debug::DebugInfo, "PNG Flush");
394 #endif // DEBUG_ENABLED
399 * Potential improvements:
400 * 1. Detect <= 256 colours and write in palette mode.
401 * 2. Detect grayscale (will early-out quickly for colour images).
402 * 3. Store colour space / gamma correction info related to the device screen?
403 * http://www.libpng.org/pub/png/book/chapter10.html
404 * 4. Refactor with callers to write straight through to disk and save keeping a big buffer around.
405 * 5. Prealloc buffer (reserve) to input size / <A number greater than 2 (expexcted few realloc but without using lots of memory) | 1 (expected zero reallocs but using a lot of memory)>.
406 * 6. Set the modification time with png_set_tIME(png_ptr, info_ptr, mod_time);
407 * 7. If caller asks for no compression, bypass libpng and blat raw data to
408 * disk, topped and tailed with header/tail blocks.
410 bool EncodeToPng( const unsigned char* const pixelBuffer, Vector<unsigned char>& encodedPixels, std::size_t width, std::size_t height, Pixel::Format pixelFormat )
412 // Translate pixel format enum:
413 int pngPixelFormat = -1;
414 unsigned pixelBytes = 0;
415 bool rgbaOrder = true;
417 // Account for RGB versus BGR and presence of alpha in input pixels:
418 switch( pixelFormat )
422 pngPixelFormat = PNG_COLOR_TYPE_RGB;
426 case Pixel::BGRA8888:
429 ///! No break: fall through:
431 case Pixel::RGBA8888:
433 pngPixelFormat = PNG_COLOR_TYPE_RGB_ALPHA;
439 DALI_LOG_ERROR( "Unsupported pixel format for encoding to PNG.\n" );
444 const int interlace = PNG_INTERLACE_NONE;
446 png_structp png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
451 /* Allocate/initialize the image information data. REQUIRED */
452 png_infop info_ptr = png_create_info_struct( png_ptr );
455 png_destroy_write_struct(&png_ptr, NULL);
459 /* Set error handling. REQUIRED if you aren't supplying your own
460 * error handling functions in the png_create_write_struct() call.
462 if(setjmp(png_jmpbuf(png_ptr)))
464 png_destroy_write_struct(&png_ptr, &info_ptr);
468 // Since we are going to write to memory instead of a file, lets provide
469 // libpng with a custom write function and ask it to pass back our
470 // Vector buffer each time it calls back to flush data to "file":
471 png_set_write_fn(png_ptr, &encodedPixels, WriteData, FlushData);
473 // png_set_compression_level( png_ptr, Z_BEST_COMPRESSION);
474 png_set_compression_level(png_ptr, Z_BEST_SPEED);
475 // png_set_compression_level( png_ptr, Z_NO_COMPRESSION); //! We could just generate png directly without libpng in this case.
477 // Explicitly limit the number of filters used per scanline to speed us up:
478 // png_set_filter(png_ptr, 0, PNG_FILTER_NONE); ///!ToDo: Try this once baseline profile is in place.
482 // PNG_FILTER_PAETH |
484 // Play with Zlib parameters in optimisation phase:
485 // png_set_compression_mem_level(png_ptr, 8);
486 // png_set_compression_strategy(png_ptr,
487 // Z_DEFAULT_STRATEGY);
488 // png_set_compression_window_bits(png_ptr, 15);
489 // png_set_compression_method(png_ptr, 8);
490 // png_set_compression_buffer_size(png_ptr, 8192)
492 // Let lib_png know if the pixel bytes are in BGR(A) order:
495 png_set_bgr( png_ptr );
498 // Set the image information:
499 png_set_IHDR(png_ptr, info_ptr, width, height, 8,
500 pngPixelFormat, interlace,
501 PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
503 // Start to output the PNG data to our buffer:
504 png_write_info(png_ptr, info_ptr);
507 const unsigned row_step = width * pixelBytes;
508 png_bytep row_ptr = const_cast<png_bytep>(pixelBuffer);
509 const png_bytep row_end = row_ptr + height * row_step;
510 for(; row_ptr < row_end; row_ptr += row_step)
512 png_write_row(png_ptr, row_ptr);
515 /* It is REQUIRED to call this to finish writing the rest of the file */
516 png_write_end(png_ptr, info_ptr);
517 /* Clean up after the write, and free any memory allocated */
518 png_destroy_write_struct(&png_ptr, &info_ptr);
522 } // namespace TizenPlatform