dll/win32/windowscodecs/pngformat.c

   1 /*
   2  * Copyright 2009 Vincent Povirk for CodeWeavers
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  17  */
  18
  19 #include "config.h"
  20 #include "wine/port.h"
  21
  22 #include <stdarg.h>
  23
  24 #ifdef HAVE_PNG_H
  25 #include <png.h>
  26 #endif
  27
  28 #define COBJMACROS
  29
  30 #include "windef.h"
  31 #include "winbase.h"
  32 #include "objbase.h"
  33 #include "wincodec.h"
  34
  35 #include "wincodecs_private.h"
  36
  37 #include "wine/debug.h"
  38 #include "wine/library.h"
  39
  40 WINE_DEFAULT_DEBUG_CHANNEL(wincodecs);
  41
  42 #ifdef SONAME_LIBPNG
  43
  44 static void *libpng_handle;
  45 #define MAKE_FUNCPTR(f) static typeof(f) * p##f
  46 MAKE_FUNCPTR(png_create_read_struct);
  47 MAKE_FUNCPTR(png_create_info_struct);
  48 MAKE_FUNCPTR(png_create_write_struct);
  49 MAKE_FUNCPTR(png_destroy_read_struct);
  50 MAKE_FUNCPTR(png_destroy_write_struct);
  51 MAKE_FUNCPTR(png_error);
  52 MAKE_FUNCPTR(png_get_bit_depth);
  53 MAKE_FUNCPTR(png_get_color_type);
  54 MAKE_FUNCPTR(png_get_error_ptr);
  55 MAKE_FUNCPTR(png_get_image_height);
  56 MAKE_FUNCPTR(png_get_image_width);
  57 MAKE_FUNCPTR(png_get_io_ptr);
  58 MAKE_FUNCPTR(png_get_pHYs);
  59 MAKE_FUNCPTR(png_get_PLTE);
  60 MAKE_FUNCPTR(png_get_tRNS);
  61 MAKE_FUNCPTR(png_set_bgr);
  62 MAKE_FUNCPTR(png_set_error_fn);
  63 #if HAVE_PNG_SET_EXPAND_GRAY_1_2_4_TO_8
  64 MAKE_FUNCPTR(png_set_expand_gray_1_2_4_to_8);
  65 #else
  66 MAKE_FUNCPTR(png_set_gray_1_2_4_to_8);
  67 #endif
  68 MAKE_FUNCPTR(png_set_filler);
  69 MAKE_FUNCPTR(png_set_gray_to_rgb);
  70 MAKE_FUNCPTR(png_set_IHDR);
  71 MAKE_FUNCPTR(png_set_pHYs);
  72 MAKE_FUNCPTR(png_set_read_fn);
  73 MAKE_FUNCPTR(png_set_strip_16);
  74 MAKE_FUNCPTR(png_set_tRNS_to_alpha);
  75 MAKE_FUNCPTR(png_set_write_fn);
  76 MAKE_FUNCPTR(png_read_end);
  77 MAKE_FUNCPTR(png_read_image);
  78 MAKE_FUNCPTR(png_read_info);
  79 MAKE_FUNCPTR(png_write_end);
  80 MAKE_FUNCPTR(png_write_info);
  81 MAKE_FUNCPTR(png_write_rows);
  82 #undef MAKE_FUNCPTR
  83
  84 static void *load_libpng(void)
  85 {
  86     if((libpng_handle = wine_dlopen(SONAME_LIBPNG, RTLD_NOW, NULL, 0)) != NULL) {
  87
  88 #define LOAD_FUNCPTR(f) \
  89     if((p##f = wine_dlsym(libpng_handle, #f, NULL, 0)) == NULL) { \
  90         libpng_handle = NULL; \
  91         return NULL; \
  92     }
  93         LOAD_FUNCPTR(png_create_read_struct);
  94         LOAD_FUNCPTR(png_create_info_struct);
  95         LOAD_FUNCPTR(png_create_write_struct);
  96         LOAD_FUNCPTR(png_destroy_read_struct);
  97         LOAD_FUNCPTR(png_destroy_write_struct);
  98         LOAD_FUNCPTR(png_error);
  99         LOAD_FUNCPTR(png_get_bit_depth);
 100         LOAD_FUNCPTR(png_get_color_type);
 101         LOAD_FUNCPTR(png_get_error_ptr);
 102         LOAD_FUNCPTR(png_get_image_height);
 103         LOAD_FUNCPTR(png_get_image_width);
 104         LOAD_FUNCPTR(png_get_io_ptr);
 105         LOAD_FUNCPTR(png_get_pHYs);
 106         LOAD_FUNCPTR(png_get_PLTE);
 107         LOAD_FUNCPTR(png_get_tRNS);
 108         LOAD_FUNCPTR(png_set_bgr);
 109         LOAD_FUNCPTR(png_set_error_fn);
 110 #if HAVE_PNG_SET_EXPAND_GRAY_1_2_4_TO_8
 111         LOAD_FUNCPTR(png_set_expand_gray_1_2_4_to_8);
 112 #else
 113         LOAD_FUNCPTR(png_set_gray_1_2_4_to_8);
 114 #endif
 115         LOAD_FUNCPTR(png_set_filler);
 116         LOAD_FUNCPTR(png_set_gray_to_rgb);
 117         LOAD_FUNCPTR(png_set_IHDR);
 118         LOAD_FUNCPTR(png_set_pHYs);
 119         LOAD_FUNCPTR(png_set_read_fn);
 120         LOAD_FUNCPTR(png_set_strip_16);
 121         LOAD_FUNCPTR(png_set_tRNS_to_alpha);
 122         LOAD_FUNCPTR(png_set_write_fn);
 123         LOAD_FUNCPTR(png_read_end);
 124         LOAD_FUNCPTR(png_read_image);
 125         LOAD_FUNCPTR(png_read_info);
 126         LOAD_FUNCPTR(png_write_end);
 127         LOAD_FUNCPTR(png_write_info);
 128         LOAD_FUNCPTR(png_write_rows);
 129
 130 #undef LOAD_FUNCPTR
 131     }
 132     return libpng_handle;
 133 }
 134
 135 static void user_error_fn(png_structp png_ptr, png_const_charp error_message)
 136 {
 137     jmp_buf *pjmpbuf;
 138
 139     /* This uses setjmp/longjmp just like the default. We can't use the
 140      * default because there's no way to access the jmp buffer in the png_struct
 141      * that works in 1.2 and 1.4 and allows us to dynamically load libpng. */
 142     WARN("PNG error: %s\n", debugstr_a(error_message));
 143     pjmpbuf = ppng_get_error_ptr(png_ptr);
 144     longjmp(*pjmpbuf, 1);
 145 }
 146
 147 static void user_warning_fn(png_structp png_ptr, png_const_charp warning_message)
 148 {
 149     WARN("PNG warning: %s\n", debugstr_a(warning_message));
 150 }
 151
 152 typedef struct {
 153     const IWICBitmapDecoderVtbl *lpVtbl;
 154     const IWICBitmapFrameDecodeVtbl *lpFrameVtbl;
 155     LONG ref;
 156     png_structp png_ptr;
 157     png_infop info_ptr;
 158     png_infop end_info;
 159     BOOL initialized;
 160     int bpp;
 161     int width, height;
 162     UINT stride;
 163     const WICPixelFormatGUID *format;
 164     BYTE *image_bits;
 165     CRITICAL_SECTION lock; /* must be held when png structures are accessed or initialized is set */
 166 } PngDecoder;
 167
 168 static inline PngDecoder *impl_from_frame(IWICBitmapFrameDecode *iface)
 169 {
 170     return CONTAINING_RECORD(iface, PngDecoder, lpFrameVtbl);
 171 }
 172
 173 static const IWICBitmapFrameDecodeVtbl PngDecoder_FrameVtbl;
 174
 175 static HRESULT WINAPI PngDecoder_QueryInterface(IWICBitmapDecoder *iface, REFIID iid,
 176     void **ppv)
 177 {
 178     PngDecoder *This = (PngDecoder*)iface;
 179     TRACE("(%p,%s,%p)\n", iface, debugstr_guid(iid), ppv);
 180
 181     if (!ppv) return E_INVALIDARG;
 182
 183     if (IsEqualIID(&IID_IUnknown, iid) || IsEqualIID(&IID_IWICBitmapDecoder, iid))
 184     {
 185         *ppv = This;
 186     }
 187     else
 188     {
 189         *ppv = NULL;
 190         return E_NOINTERFACE;
 191     }
 192
 193     IUnknown_AddRef((IUnknown*)*ppv);
 194     return S_OK;
 195 }
 196
 197 static ULONG WINAPI PngDecoder_AddRef(IWICBitmapDecoder *iface)
 198 {
 199     PngDecoder *This = (PngDecoder*)iface;
 200     ULONG ref = InterlockedIncrement(&This->ref);
 201
 202     TRACE("(%p) refcount=%u\n", iface, ref);
 203
 204     return ref;
 205 }
 206
 207 static ULONG WINAPI PngDecoder_Release(IWICBitmapDecoder *iface)
 208 {
 209     PngDecoder *This = (PngDecoder*)iface;
 210     ULONG ref = InterlockedDecrement(&This->ref);
 211
 212     TRACE("(%p) refcount=%u\n", iface, ref);
 213
 214     if (ref == 0)
 215     {
 216         if (This->png_ptr)
 217             ppng_destroy_read_struct(&This->png_ptr, &This->info_ptr, &This->end_info);
 218         This->lock.DebugInfo->Spare[0] = 0;
 219         DeleteCriticalSection(&This->lock);
 220         HeapFree(GetProcessHeap(), 0, This->image_bits);
 221         HeapFree(GetProcessHeap(), 0, This);
 222     }
 223
 224     return ref;
 225 }
 226
 227 static HRESULT WINAPI PngDecoder_QueryCapability(IWICBitmapDecoder *iface, IStream *pIStream,
 228     DWORD *pdwCapability)
 229 {
 230     FIXME("(%p,%p,%p): stub\n", iface, pIStream, pdwCapability);
 231     return E_NOTIMPL;
 232 }
 233
 234 static void user_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
 235 {
 236     IStream *stream = ppng_get_io_ptr(png_ptr);
 237     HRESULT hr;
 238     ULONG bytesread;
 239
 240     hr = IStream_Read(stream, data, length, &bytesread);
 241     if (FAILED(hr) || bytesread != length)
 242     {
 243         ppng_error(png_ptr, "failed reading data");
 244     }
 245 }
 246
 247 static HRESULT WINAPI PngDecoder_Initialize(IWICBitmapDecoder *iface, IStream *pIStream,
 248     WICDecodeOptions cacheOptions)
 249 {
 250     PngDecoder *This = (PngDecoder*)iface;
 251     LARGE_INTEGER seek;
 252     HRESULT hr=S_OK;
 253     png_bytep *row_pointers=NULL;
 254     UINT image_size;
 255     UINT i;
 256     int color_type, bit_depth;
 257     png_bytep trans;
 258     int num_trans;
 259     png_uint_32 transparency;
 260     png_color_16p trans_values;
 261     jmp_buf jmpbuf;
 262
 263     TRACE("(%p,%p,%x)\n", iface, pIStream, cacheOptions);
 264
 265     EnterCriticalSection(&This->lock);
 266
 267     /* initialize libpng */
 268     This->png_ptr = ppng_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
 269     if (!This->png_ptr)
 270     {
 271         hr = E_FAIL;
 272         goto end;
 273     }
 274
 275     This->info_ptr = ppng_create_info_struct(This->png_ptr);
 276     if (!This->info_ptr)
 277     {
 278         ppng_destroy_read_struct(&This->png_ptr, NULL, NULL);
 279         This->png_ptr = NULL;
 280         hr = E_FAIL;
 281         goto end;
 282     }
 283
 284     This->end_info = ppng_create_info_struct(This->png_ptr);
 285     if (!This->info_ptr)
 286     {
 287         ppng_destroy_read_struct(&This->png_ptr, &This->info_ptr, NULL);
 288         This->png_ptr = NULL;
 289         hr = E_FAIL;
 290         goto end;
 291     }
 292
 293     /* set up setjmp/longjmp error handling */
 294     if (setjmp(jmpbuf))
 295     {
 296         ppng_destroy_read_struct(&This->png_ptr, &This->info_ptr, &This->end_info);
 297         HeapFree(GetProcessHeap(), 0, row_pointers);
 298         This->png_ptr = NULL;
 299         hr = E_FAIL;
 300         goto end;
 301     }
 302     ppng_set_error_fn(This->png_ptr, &jmpbuf, user_error_fn, user_warning_fn);
 303
 304     /* seek to the start of the stream */
 305     seek.QuadPart = 0;
 306     hr = IStream_Seek(pIStream, seek, STREAM_SEEK_SET, NULL);
 307     if (FAILED(hr)) goto end;
 308
 309     /* set up custom i/o handling */
 310     ppng_set_read_fn(This->png_ptr, pIStream, user_read_data);
 311
 312     /* read the header */
 313     ppng_read_info(This->png_ptr, This->info_ptr);
 314
 315     /* choose a pixel format */
 316     color_type = ppng_get_color_type(This->png_ptr, This->info_ptr);
 317     bit_depth = ppng_get_bit_depth(This->png_ptr, This->info_ptr);
 318
 319     /* check for color-keyed alpha */
 320     transparency = ppng_get_tRNS(This->png_ptr, This->info_ptr, &trans, &num_trans, &trans_values);
 321
 322     if (transparency && color_type != PNG_COLOR_TYPE_PALETTE)
 323     {
 324         /* expand to RGBA */
 325         if (color_type == PNG_COLOR_TYPE_GRAY)
 326         {
 327             if (bit_depth < 8)
 328             {
 329 #if HAVE_PNG_SET_EXPAND_GRAY_1_2_4_TO_8
 330                 ppng_set_expand_gray_1_2_4_to_8(This->png_ptr);
 331 #else
 332                 ppng_set_gray_1_2_4_to_8(This->png_ptr);
 333 #endif
 334                 bit_depth = 8;
 335             }
 336             ppng_set_gray_to_rgb(This->png_ptr);
 337         }
 338         ppng_set_tRNS_to_alpha(This->png_ptr);
 339         color_type = PNG_COLOR_TYPE_RGB_ALPHA;
 340     }
 341
 342     switch (color_type)
 343     {
 344     case PNG_COLOR_TYPE_GRAY:
 345         This->bpp = bit_depth;
 346         switch (bit_depth)
 347         {
 348         case 1: This->format = &GUID_WICPixelFormatBlackWhite; break;
 349         case 2: This->format = &GUID_WICPixelFormat2bppGray; break;
 350         case 4: This->format = &GUID_WICPixelFormat4bppGray; break;
 351         case 8: This->format = &GUID_WICPixelFormat8bppGray; break;
 352         case 16: This->format = &GUID_WICPixelFormat16bppGray; break;
 353         default:
 354             ERR("invalid grayscale bit depth: %i\n", bit_depth);
 355             hr = E_FAIL;
 356             goto end;
 357         }
 358         break;
 359     case PNG_COLOR_TYPE_GRAY_ALPHA:
 360         /* WIC does not support grayscale alpha formats so use RGBA */
 361         ppng_set_gray_to_rgb(This->png_ptr);
 362     case PNG_COLOR_TYPE_RGB_ALPHA:
 363         This->bpp = bit_depth * 4;
 364         switch (bit_depth)
 365         {
 366         case 8:
 367             ppng_set_bgr(This->png_ptr);
 368             This->format = &GUID_WICPixelFormat32bppBGRA;
 369             break;
 370         case 16: This->format = &GUID_WICPixelFormat64bppRGBA; break;
 371         default:
 372             ERR("invalid RGBA bit depth: %i\n", bit_depth);
 373             hr = E_FAIL;
 374             goto end;
 375         }
 376         break;
 377     case PNG_COLOR_TYPE_PALETTE:
 378         This->bpp = bit_depth;
 379         switch (bit_depth)
 380         {
 381         case 1: This->format = &GUID_WICPixelFormat1bppIndexed; break;
 382         case 2: This->format = &GUID_WICPixelFormat2bppIndexed; break;
 383         case 4: This->format = &GUID_WICPixelFormat4bppIndexed; break;
 384         case 8: This->format = &GUID_WICPixelFormat8bppIndexed; break;
 385         default:
 386             ERR("invalid indexed color bit depth: %i\n", bit_depth);
 387             hr = E_FAIL;
 388             goto end;
 389         }
 390         break;
 391     case PNG_COLOR_TYPE_RGB:
 392         This->bpp = bit_depth * 3;
 393         switch (bit_depth)
 394         {
 395         case 8:
 396             ppng_set_bgr(This->png_ptr);
 397             This->format = &GUID_WICPixelFormat24bppBGR;
 398             break;
 399         case 16: This->format = &GUID_WICPixelFormat48bppRGB; break;
 400         default:
 401             ERR("invalid RGB color bit depth: %i\n", bit_depth);
 402             hr = E_FAIL;
 403             goto end;
 404         }
 405         break;
 406     default:
 407         ERR("invalid color type %i\n", color_type);
 408         hr = E_FAIL;
 409         goto end;
 410     }
 411
 412     /* read the image data */
 413     This->width = ppng_get_image_width(This->png_ptr, This->info_ptr);
 414     This->height = ppng_get_image_height(This->png_ptr, This->info_ptr);
 415     This->stride = This->width * This->bpp;
 416     image_size = This->stride * This->height;
 417
 418     This->image_bits = HeapAlloc(GetProcessHeap(), 0, image_size);
 419     if (!This->image_bits)
 420     {
 421         hr = E_OUTOFMEMORY;
 422         goto end;
 423     }
 424
 425     row_pointers = HeapAlloc(GetProcessHeap(), 0, sizeof(png_bytep)*This->height);
 426     if (!row_pointers)
 427     {
 428         hr = E_OUTOFMEMORY;
 429         goto end;
 430     }
 431
 432     for (i=0; i<This->height; i++)
 433         row_pointers[i] = This->image_bits + i * This->stride;
 434
 435     ppng_read_image(This->png_ptr, row_pointers);
 436
 437     HeapFree(GetProcessHeap(), 0, row_pointers);
 438     row_pointers = NULL;
 439
 440     ppng_read_end(This->png_ptr, This->end_info);
 441
 442     This->initialized = TRUE;
 443
 444 end:
 445
 446     LeaveCriticalSection(&This->lock);
 447
 448     return hr;
 449 }
 450
 451 static HRESULT WINAPI PngDecoder_GetContainerFormat(IWICBitmapDecoder *iface,
 452     GUID *pguidContainerFormat)
 453 {
 454     memcpy(pguidContainerFormat, &GUID_ContainerFormatPng, sizeof(GUID));
 455     return S_OK;
 456 }
 457
 458 static HRESULT WINAPI PngDecoder_GetDecoderInfo(IWICBitmapDecoder *iface,
 459     IWICBitmapDecoderInfo **ppIDecoderInfo)
 460 {
 461     FIXME("(%p,%p): stub\n", iface, ppIDecoderInfo);
 462     return E_NOTIMPL;
 463 }
 464
 465 static HRESULT WINAPI PngDecoder_CopyPalette(IWICBitmapDecoder *iface,
 466     IWICPalette *pIPalette)
 467 {
 468     FIXME("(%p,%p): stub\n", iface, pIPalette);
 469     return E_NOTIMPL;
 470 }
 471
 472 static HRESULT WINAPI PngDecoder_GetMetadataQueryReader(IWICBitmapDecoder *iface,
 473     IWICMetadataQueryReader **ppIMetadataQueryReader)
 474 {
 475     FIXME("(%p,%p): stub\n", iface, ppIMetadataQueryReader);
 476     return E_NOTIMPL;
 477 }
 478
 479 static HRESULT WINAPI PngDecoder_GetPreview(IWICBitmapDecoder *iface,
 480     IWICBitmapSource **ppIBitmapSource)
 481 {
 482     FIXME("(%p,%p): stub\n", iface, ppIBitmapSource);
 483     return E_NOTIMPL;
 484 }
 485
 486 static HRESULT WINAPI PngDecoder_GetColorContexts(IWICBitmapDecoder *iface,
 487     UINT cCount, IWICColorContext **ppIColorContexts, UINT *pcActualCount)
 488 {
 489     FIXME("(%p,%u,%p,%p)\n", iface, cCount, ppIColorContexts, pcActualCount);
 490     return E_NOTIMPL;
 491 }
 492
 493 static HRESULT WINAPI PngDecoder_GetThumbnail(IWICBitmapDecoder *iface,
 494     IWICBitmapSource **ppIThumbnail)
 495 {
 496     TRACE("(%p,%p)\n", iface, ppIThumbnail);
 497     return WINCODEC_ERR_CODECNOTHUMBNAIL;
 498 }
 499
 500 static HRESULT WINAPI PngDecoder_GetFrameCount(IWICBitmapDecoder *iface,
 501     UINT *pCount)
 502 {
 503     *pCount = 1;
 504     return S_OK;
 505 }
 506
 507 static HRESULT WINAPI PngDecoder_GetFrame(IWICBitmapDecoder *iface,
 508     UINT index, IWICBitmapFrameDecode **ppIBitmapFrame)
 509 {
 510     PngDecoder *This = (PngDecoder*)iface;
 511     TRACE("(%p,%u,%p)\n", iface, index, ppIBitmapFrame);
 512
 513     if (!This->initialized) return WINCODEC_ERR_NOTINITIALIZED;
 514
 515     if (index != 0) return E_INVALIDARG;
 516
 517     IWICBitmapDecoder_AddRef(iface);
 518
 519     *ppIBitmapFrame = (void*)(&This->lpFrameVtbl);
 520
 521     return S_OK;
 522 }
 523
 524 static const IWICBitmapDecoderVtbl PngDecoder_Vtbl = {
 525     PngDecoder_QueryInterface,
 526     PngDecoder_AddRef,
 527     PngDecoder_Release,
 528     PngDecoder_QueryCapability,
 529     PngDecoder_Initialize,
 530     PngDecoder_GetContainerFormat,
 531     PngDecoder_GetDecoderInfo,
 532     PngDecoder_CopyPalette,
 533     PngDecoder_GetMetadataQueryReader,
 534     PngDecoder_GetPreview,
 535     PngDecoder_GetColorContexts,
 536     PngDecoder_GetThumbnail,
 537     PngDecoder_GetFrameCount,
 538     PngDecoder_GetFrame
 539 };
 540
 541 static HRESULT WINAPI PngDecoder_Frame_QueryInterface(IWICBitmapFrameDecode *iface, REFIID iid,
 542     void **ppv)
 543 {
 544     if (!ppv) return E_INVALIDARG;
 545
 546     if (IsEqualIID(&IID_IUnknown, iid) ||
 547         IsEqualIID(&IID_IWICBitmapSource, iid) ||
 548         IsEqualIID(&IID_IWICBitmapFrameDecode, iid))
 549     {
 550         *ppv = iface;
 551     }
 552     else
 553     {
 554         *ppv = NULL;
 555         return E_NOINTERFACE;
 556     }
 557
 558     IUnknown_AddRef((IUnknown*)*ppv);
 559     return S_OK;
 560 }
 561
 562 static ULONG WINAPI PngDecoder_Frame_AddRef(IWICBitmapFrameDecode *iface)
 563 {
 564     PngDecoder *This = impl_from_frame(iface);
 565     return IUnknown_AddRef((IUnknown*)This);
 566 }
 567
 568 static ULONG WINAPI PngDecoder_Frame_Release(IWICBitmapFrameDecode *iface)
 569 {
 570     PngDecoder *This = impl_from_frame(iface);
 571     return IUnknown_Release((IUnknown*)This);
 572 }
 573
 574 static HRESULT WINAPI PngDecoder_Frame_GetSize(IWICBitmapFrameDecode *iface,
 575     UINT *puiWidth, UINT *puiHeight)
 576 {
 577     PngDecoder *This = impl_from_frame(iface);
 578     *puiWidth = This->width;
 579     *puiHeight = This->height;
 580     TRACE("(%p)->(%u,%u)\n", iface, *puiWidth, *puiHeight);
 581     return S_OK;
 582 }
 583
 584 static HRESULT WINAPI PngDecoder_Frame_GetPixelFormat(IWICBitmapFrameDecode *iface,
 585     WICPixelFormatGUID *pPixelFormat)
 586 {
 587     PngDecoder *This = impl_from_frame(iface);
 588     TRACE("(%p,%p)\n", iface, pPixelFormat);
 589
 590     memcpy(pPixelFormat, This->format, sizeof(GUID));
 591
 592     return S_OK;
 593 }
 594
 595 static HRESULT WINAPI PngDecoder_Frame_GetResolution(IWICBitmapFrameDecode *iface,
 596     double *pDpiX, double *pDpiY)
 597 {
 598     PngDecoder *This = impl_from_frame(iface);
 599     png_uint_32 ret, xres, yres;
 600     int unit_type;
 601
 602     EnterCriticalSection(&This->lock);
 603
 604     ret = ppng_get_pHYs(This->png_ptr, This->info_ptr, &xres, &yres, &unit_type);
 605
 606     if (ret && unit_type == PNG_RESOLUTION_METER)
 607     {
 608         *pDpiX = xres * 0.0254;
 609         *pDpiY = yres * 0.0254;
 610     }
 611     else
 612     {
 613         WARN("no pHYs block present\n");
 614         *pDpiX = *pDpiY = 96.0;
 615     }
 616
 617     LeaveCriticalSection(&This->lock);
 618
 619     TRACE("(%p)->(%0.2f,%0.2f)\n", iface, *pDpiX, *pDpiY);
 620
 621     return S_OK;
 622 }
 623
 624 static HRESULT WINAPI PngDecoder_Frame_CopyPalette(IWICBitmapFrameDecode *iface,
 625     IWICPalette *pIPalette)
 626 {
 627     PngDecoder *This = impl_from_frame(iface);
 628     png_uint_32 ret;
 629     png_colorp png_palette;
 630     int num_palette;
 631     WICColor palette[256];
 632     png_bytep trans;
 633     int num_trans;
 634     png_color_16p trans_values;
 635     int i;
 636     HRESULT hr=S_OK;
 637
 638     TRACE("(%p,%p)\n", iface, pIPalette);
 639
 640     EnterCriticalSection(&This->lock);
 641
 642     ret = ppng_get_PLTE(This->png_ptr, This->info_ptr, &png_palette, &num_palette);
 643     if (!ret)
 644     {
 645         hr = WINCODEC_ERR_PALETTEUNAVAILABLE;
 646         goto end;
 647     }
 648
 649     if (num_palette > 256)
 650     {
 651         ERR("palette has %i colors?!\n", num_palette);
 652         hr = E_FAIL;
 653         goto end;
 654     }
 655
 656     for (i=0; i<num_palette; i++)
 657     {
 658         palette[i] = (0xff000000|
 659                       png_palette[i].red << 16|
 660                       png_palette[i].green << 8|
 661                       png_palette[i].blue);
 662     }
 663
 664     ret = ppng_get_tRNS(This->png_ptr, This->info_ptr, &trans, &num_trans, &trans_values);
 665     if (ret)
 666     {
 667         for (i=0; i<num_trans; i++)
 668         {
 669             palette[trans[i]] = 0x00000000;
 670         }
 671     }
 672
 673 end:
 674
 675     LeaveCriticalSection(&This->lock);
 676
 677     if (SUCCEEDED(hr))
 678         hr = IWICPalette_InitializeCustom(pIPalette, palette, num_palette);
 679
 680     return hr;
 681 }
 682
 683 static HRESULT WINAPI PngDecoder_Frame_CopyPixels(IWICBitmapFrameDecode *iface,
 684     const WICRect *prc, UINT cbStride, UINT cbBufferSize, BYTE *pbBuffer)
 685 {
 686     PngDecoder *This = impl_from_frame(iface);
 687     TRACE("(%p,%p,%u,%u,%p)\n", iface, prc, cbStride, cbBufferSize, pbBuffer);
 688
 689     return copy_pixels(This->bpp, This->image_bits,
 690         This->width, This->height, This->stride,
 691         prc, cbStride, cbBufferSize, pbBuffer);
 692 }
 693
 694 static HRESULT WINAPI PngDecoder_Frame_GetMetadataQueryReader(IWICBitmapFrameDecode *iface,
 695     IWICMetadataQueryReader **ppIMetadataQueryReader)
 696 {
 697     FIXME("(%p,%p): stub\n", iface, ppIMetadataQueryReader);
 698     return E_NOTIMPL;
 699 }
 700
 701 static HRESULT WINAPI PngDecoder_Frame_GetColorContexts(IWICBitmapFrameDecode *iface,
 702     UINT cCount, IWICColorContext **ppIColorContexts, UINT *pcActualCount)
 703 {
 704     FIXME("(%p,%u,%p,%p): stub\n", iface, cCount, ppIColorContexts, pcActualCount);
 705     return E_NOTIMPL;
 706 }
 707
 708 static HRESULT WINAPI PngDecoder_Frame_GetThumbnail(IWICBitmapFrameDecode *iface,
 709     IWICBitmapSource **ppIThumbnail)
 710 {
 711     FIXME("(%p,%p): stub\n", iface, ppIThumbnail);
 712     return E_NOTIMPL;
 713 }
 714
 715 static const IWICBitmapFrameDecodeVtbl PngDecoder_FrameVtbl = {
 716     PngDecoder_Frame_QueryInterface,
 717     PngDecoder_Frame_AddRef,
 718     PngDecoder_Frame_Release,
 719     PngDecoder_Frame_GetSize,
 720     PngDecoder_Frame_GetPixelFormat,
 721     PngDecoder_Frame_GetResolution,
 722     PngDecoder_Frame_CopyPalette,
 723     PngDecoder_Frame_CopyPixels,
 724     PngDecoder_Frame_GetMetadataQueryReader,
 725     PngDecoder_Frame_GetColorContexts,
 726     PngDecoder_Frame_GetThumbnail
 727 };
 728
 729 HRESULT PngDecoder_CreateInstance(IUnknown *pUnkOuter, REFIID iid, void** ppv)
 730 {
 731     PngDecoder *This;
 732     HRESULT ret;
 733
 734     TRACE("(%p,%s,%p)\n", pUnkOuter, debugstr_guid(iid), ppv);
 735
 736     *ppv = NULL;
 737
 738     if (pUnkOuter) return CLASS_E_NOAGGREGATION;
 739
 740     if (!libpng_handle && !load_libpng())
 741     {
 742         ERR("Failed reading PNG because unable to find %s\n",SONAME_LIBPNG);
 743         return E_FAIL;
 744     }
 745
 746     This = HeapAlloc(GetProcessHeap(), 0, sizeof(PngDecoder));
 747     if (!This) return E_OUTOFMEMORY;
 748
 749     This->lpVtbl = &PngDecoder_Vtbl;
 750     This->lpFrameVtbl = &PngDecoder_FrameVtbl;
 751     This->ref = 1;
 752     This->png_ptr = NULL;
 753     This->info_ptr = NULL;
 754     This->end_info = NULL;
 755     This->initialized = FALSE;
 756     This->image_bits = NULL;
 757     InitializeCriticalSection(&This->lock);
 758     This->lock.DebugInfo->Spare[0] = (DWORD_PTR)(__FILE__ ": PngDecoder.lock");
 759
 760     ret = IUnknown_QueryInterface((IUnknown*)This, iid, ppv);
 761     IUnknown_Release((IUnknown*)This);
 762
 763     return ret;
 764 }
 765
 766 struct png_pixelformat {
 767     const WICPixelFormatGUID *guid;
 768     UINT bpp;
 769     int bit_depth;
 770     int color_type;
 771     BOOL remove_filler;
 772     BOOL swap_rgb;
 773 };
 774
 775 static const struct png_pixelformat formats[] = {
 776     {&GUID_WICPixelFormat24bppBGR, 24, 8, PNG_COLOR_TYPE_RGB, 0, 1},
 777     {&GUID_WICPixelFormatBlackWhite, 1, 1, PNG_COLOR_TYPE_GRAY, 0, 0},
 778     {&GUID_WICPixelFormat2bppGray, 2, 2, PNG_COLOR_TYPE_GRAY, 0, 0},
 779     {&GUID_WICPixelFormat4bppGray, 4, 4, PNG_COLOR_TYPE_GRAY, 0, 0},
 780     {&GUID_WICPixelFormat8bppGray, 8, 8, PNG_COLOR_TYPE_GRAY, 0, 0},
 781     {&GUID_WICPixelFormat16bppGray, 16, 16, PNG_COLOR_TYPE_GRAY, 0, 0},
 782     {&GUID_WICPixelFormat32bppBGR, 32, 8, PNG_COLOR_TYPE_RGB, 1, 1},
 783     {&GUID_WICPixelFormat32bppBGRA, 32, 8, PNG_COLOR_TYPE_RGB_ALPHA, 0, 1},
 784     {&GUID_WICPixelFormat48bppRGB, 48, 16, PNG_COLOR_TYPE_RGB, 0, 0},
 785     {&GUID_WICPixelFormat64bppRGBA, 64, 16, PNG_COLOR_TYPE_RGB_ALPHA, 0, 0},
 786     {NULL},
 787 };
 788
 789 typedef struct PngEncoder {
 790     const IWICBitmapEncoderVtbl *lpVtbl;
 791     const IWICBitmapFrameEncodeVtbl *lpFrameVtbl;
 792     LONG ref;
 793     IStream *stream;
 794     png_structp png_ptr;
 795     png_infop info_ptr;
 796     UINT frame_count;
 797     BOOL frame_initialized;
 798     const struct png_pixelformat *format;
 799     BOOL info_written;
 800     UINT width, height;
 801     double xres, yres;
 802     UINT lines_written;
 803     BOOL frame_committed;
 804     BOOL committed;
 805     CRITICAL_SECTION lock;
 806 } PngEncoder;
 807
 808 static inline PngEncoder *encoder_from_frame(IWICBitmapFrameEncode *iface)
 809 {
 810     return CONTAINING_RECORD(iface, PngEncoder, lpFrameVtbl);
 811 }
 812
 813 static HRESULT WINAPI PngFrameEncode_QueryInterface(IWICBitmapFrameEncode *iface, REFIID iid,
 814     void **ppv)
 815 {
 816     PngEncoder *This = encoder_from_frame(iface);
 817     TRACE("(%p,%s,%p)\n", iface, debugstr_guid(iid), ppv);
 818
 819     if (!ppv) return E_INVALIDARG;
 820
 821     if (IsEqualIID(&IID_IUnknown, iid) ||
 822         IsEqualIID(&IID_IWICBitmapFrameEncode, iid))
 823     {
 824         *ppv = &This->lpFrameVtbl;
 825     }
 826     else
 827     {
 828         *ppv = NULL;
 829         return E_NOINTERFACE;
 830     }
 831
 832     IUnknown_AddRef((IUnknown*)*ppv);
 833     return S_OK;
 834 }
 835
 836 static ULONG WINAPI PngFrameEncode_AddRef(IWICBitmapFrameEncode *iface)
 837 {
 838     PngEncoder *This = encoder_from_frame(iface);
 839     return IUnknown_AddRef((IUnknown*)This);
 840 }
 841
 842 static ULONG WINAPI PngFrameEncode_Release(IWICBitmapFrameEncode *iface)
 843 {
 844     PngEncoder *This = encoder_from_frame(iface);
 845     return IUnknown_Release((IUnknown*)This);
 846 }
 847
 848 static HRESULT WINAPI PngFrameEncode_Initialize(IWICBitmapFrameEncode *iface,
 849     IPropertyBag2 *pIEncoderOptions)
 850 {
 851     PngEncoder *This = encoder_from_frame(iface);
 852     TRACE("(%p,%p)\n", iface, pIEncoderOptions);
 853
 854     EnterCriticalSection(&This->lock);
 855
 856     if (This->frame_initialized)
 857     {
 858         LeaveCriticalSection(&This->lock);
 859         return WINCODEC_ERR_WRONGSTATE;
 860     }
 861
 862     This->frame_initialized = TRUE;
 863
 864     LeaveCriticalSection(&This->lock);
 865
 866     return S_OK;
 867 }
 868
 869 static HRESULT WINAPI PngFrameEncode_SetSize(IWICBitmapFrameEncode *iface,
 870     UINT uiWidth, UINT uiHeight)
 871 {
 872     PngEncoder *This = encoder_from_frame(iface);
 873     TRACE("(%p,%u,%u)\n", iface, uiWidth, uiHeight);
 874
 875     EnterCriticalSection(&This->lock);
 876
 877     if (!This->frame_initialized || This->info_written)
 878     {
 879         LeaveCriticalSection(&This->lock);
 880         return WINCODEC_ERR_WRONGSTATE;
 881     }
 882
 883     This->width = uiWidth;
 884     This->height = uiHeight;
 885
 886     LeaveCriticalSection(&This->lock);
 887
 888     return S_OK;
 889 }
 890
 891 static HRESULT WINAPI PngFrameEncode_SetResolution(IWICBitmapFrameEncode *iface,
 892     double dpiX, double dpiY)
 893 {
 894     PngEncoder *This = encoder_from_frame(iface);
 895     TRACE("(%p,%0.2f,%0.2f)\n", iface, dpiX, dpiY);
 896
 897     EnterCriticalSection(&This->lock);
 898
 899     if (!This->frame_initialized || This->info_written)
 900     {
 901         LeaveCriticalSection(&This->lock);
 902         return WINCODEC_ERR_WRONGSTATE;
 903     }
 904
 905     This->xres = dpiX;
 906     This->yres = dpiY;
 907
 908     LeaveCriticalSection(&This->lock);
 909
 910     return S_OK;
 911 }
 912
 913 static HRESULT WINAPI PngFrameEncode_SetPixelFormat(IWICBitmapFrameEncode *iface,
 914     WICPixelFormatGUID *pPixelFormat)
 915 {
 916     PngEncoder *This = encoder_from_frame(iface);
 917     int i;
 918     TRACE("(%p,%s)\n", iface, debugstr_guid(pPixelFormat));
 919
 920     EnterCriticalSection(&This->lock);
 921
 922     if (!This->frame_initialized || This->info_written)
 923     {
 924         LeaveCriticalSection(&This->lock);
 925         return WINCODEC_ERR_WRONGSTATE;
 926     }
 927
 928     for (i=0; formats[i].guid; i++)
 929     {
 930         if (memcmp(formats[i].guid, pPixelFormat, sizeof(GUID)) == 0)
 931             break;
 932     }
 933
 934     if (!formats[i].guid) i = 0;
 935
 936     This->format = &formats[i];
 937     memcpy(pPixelFormat, This->format->guid, sizeof(GUID));
 938
 939     LeaveCriticalSection(&This->lock);
 940
 941     return S_OK;
 942 }
 943
 944 static HRESULT WINAPI PngFrameEncode_SetColorContexts(IWICBitmapFrameEncode *iface,
 945     UINT cCount, IWICColorContext **ppIColorContext)
 946 {
 947     FIXME("(%p,%u,%p): stub\n", iface, cCount, ppIColorContext);
 948     return E_NOTIMPL;
 949 }
 950
 951 static HRESULT WINAPI PngFrameEncode_SetPalette(IWICBitmapFrameEncode *iface,
 952     IWICPalette *pIPalette)
 953 {
 954     FIXME("(%p,%p): stub\n", iface, pIPalette);
 955     return WINCODEC_ERR_UNSUPPORTEDOPERATION;
 956 }
 957
 958 static HRESULT WINAPI PngFrameEncode_SetThumbnail(IWICBitmapFrameEncode *iface,
 959     IWICBitmapSource *pIThumbnail)
 960 {
 961     FIXME("(%p,%p): stub\n", iface, pIThumbnail);
 962     return WINCODEC_ERR_UNSUPPORTEDOPERATION;
 963 }
 964
 965 static HRESULT WINAPI PngFrameEncode_WritePixels(IWICBitmapFrameEncode *iface,
 966     UINT lineCount, UINT cbStride, UINT cbBufferSize, BYTE *pbPixels)
 967 {
 968     PngEncoder *This = encoder_from_frame(iface);
 969     png_byte **row_pointers=NULL;
 970     UINT i;
 971     jmp_buf jmpbuf;
 972     TRACE("(%p,%u,%u,%u,%p)\n", iface, lineCount, cbStride, cbBufferSize, pbPixels);
 973
 974     EnterCriticalSection(&This->lock);
 975
 976     if (!This->frame_initialized || !This->width || !This->height || !This->format)
 977     {
 978         LeaveCriticalSection(&This->lock);
 979         return WINCODEC_ERR_WRONGSTATE;
 980     }
 981
 982     if (lineCount == 0 || lineCount + This->lines_written > This->height)
 983     {
 984         LeaveCriticalSection(&This->lock);
 985         return E_INVALIDARG;
 986     }
 987
 988     /* set up setjmp/longjmp error handling */
 989     if (setjmp(jmpbuf))
 990     {
 991         LeaveCriticalSection(&This->lock);
 992         HeapFree(GetProcessHeap(), 0, row_pointers);
 993         return E_FAIL;
 994     }
 995     ppng_set_error_fn(This->png_ptr, &jmpbuf, user_error_fn, user_warning_fn);
 996
 997     if (!This->info_written)
 998     {
 999         ppng_set_IHDR(This->png_ptr, This->info_ptr, This->width, This->height,
1000             This->format->bit_depth, This->format->color_type, PNG_INTERLACE_NONE,
1001             PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
1002
1003         if (This->xres != 0.0 && This->yres != 0.0)
1004         {
1005             ppng_set_pHYs(This->png_ptr, This->info_ptr, (This->xres+0.0127) / 0.0254,
1006                 (This->yres+0.0127) / 0.0254, PNG_RESOLUTION_METER);
1007         }
1008
1009         ppng_write_info(This->png_ptr, This->info_ptr);
1010
1011         if (This->format->remove_filler)
1012             ppng_set_filler(This->png_ptr, 0, PNG_FILLER_AFTER);
1013
1014         if (This->format->swap_rgb)
1015             ppng_set_bgr(This->png_ptr);
1016
1017         This->info_written = TRUE;
1018     }
1019
1020     row_pointers = HeapAlloc(GetProcessHeap(), 0, lineCount * sizeof(png_byte*));
1021     if (!row_pointers)
1022     {
1023         LeaveCriticalSection(&This->lock);
1024         return E_OUTOFMEMORY;
1025     }
1026
1027     for (i=0; i<lineCount; i++)
1028         row_pointers[i] = pbPixels + cbStride * i;
1029
1030     ppng_write_rows(This->png_ptr, row_pointers, lineCount);
1031     This->lines_written += lineCount;
1032
1033     LeaveCriticalSection(&This->lock);
1034
1035     HeapFree(GetProcessHeap(), 0, row_pointers);
1036
1037     return S_OK;
1038 }
1039
1040 static HRESULT WINAPI PngFrameEncode_WriteSource(IWICBitmapFrameEncode *iface,
1041     IWICBitmapSource *pIBitmapSource, WICRect *prc)
1042 {
1043     PngEncoder *This = encoder_from_frame(iface);
1044     HRESULT hr;
1045     WICRect rc;
1046     WICPixelFormatGUID guid;
1047     UINT stride;
1048     BYTE *pixeldata;
1049     TRACE("(%p,%p,%p)\n", iface, pIBitmapSource, prc);
1050
1051     if (!This->frame_initialized || !This->width || !This->height)
1052         return WINCODEC_ERR_WRONGSTATE;
1053
1054     if (!This->format)
1055     {
1056         hr = IWICBitmapSource_GetPixelFormat(pIBitmapSource, &guid);
1057         if (FAILED(hr)) return hr;
1058         hr = IWICBitmapFrameEncode_SetPixelFormat(iface, &guid);
1059         if (FAILED(hr)) return hr;
1060     }
1061
1062     hr = IWICBitmapSource_GetPixelFormat(pIBitmapSource, &guid);
1063     if (FAILED(hr)) return hr;
1064     if (memcmp(&guid, This->format->guid, sizeof(GUID)) != 0)
1065     {
1066         /* FIXME: should use WICConvertBitmapSource to convert */
1067         ERR("format %s unsupported\n", debugstr_guid(&guid));
1068         return E_FAIL;
1069     }
1070
1071     if (This->xres == 0.0 || This->yres == 0.0)
1072     {
1073         double xres, yres;
1074         hr = IWICBitmapSource_GetResolution(pIBitmapSource, &xres, &yres);
1075         if (FAILED(hr)) return hr;
1076         hr = IWICBitmapFrameEncode_SetResolution(iface, xres, yres);
1077         if (FAILED(hr)) return hr;
1078     }
1079
1080     if (!prc)
1081     {
1082         UINT width, height;
1083         hr = IWICBitmapSource_GetSize(pIBitmapSource, &width, &height);
1084         if (FAILED(hr)) return hr;
1085         rc.X = 0;
1086         rc.Y = 0;
1087         rc.Width = width;
1088         rc.Height = height;
1089         prc = &rc;
1090     }
1091
1092     if (prc->Width != This->width) return E_INVALIDARG;
1093
1094     stride = (This->format->bpp * This->width + 7)/8;
1095
1096     pixeldata = HeapAlloc(GetProcessHeap(), 0, stride * prc->Height);
1097     if (!pixeldata) return E_OUTOFMEMORY;
1098
1099     hr = IWICBitmapSource_CopyPixels(pIBitmapSource, prc, stride,
1100         stride*prc->Height, pixeldata);
1101
1102     if (SUCCEEDED(hr))
1103     {
1104         hr = IWICBitmapFrameEncode_WritePixels(iface, prc->Height, stride,
1105             stride*prc->Height, pixeldata);
1106     }
1107
1108     HeapFree(GetProcessHeap(), 0, pixeldata);
1109
1110     return hr;
1111 }
1112
1113 static HRESULT WINAPI PngFrameEncode_Commit(IWICBitmapFrameEncode *iface)
1114 {
1115     PngEncoder *This = encoder_from_frame(iface);
1116     jmp_buf jmpbuf;
1117     TRACE("(%p)\n", iface);
1118
1119     EnterCriticalSection(&This->lock);
1120
1121     if (!This->info_written || This->lines_written != This->height || This->frame_committed)
1122     {
1123         LeaveCriticalSection(&This->lock);
1124         return WINCODEC_ERR_WRONGSTATE;
1125     }
1126
1127     /* set up setjmp/longjmp error handling */
1128     if (setjmp(jmpbuf))
1129     {
1130         LeaveCriticalSection(&This->lock);
1131         return E_FAIL;
1132     }
1133     ppng_set_error_fn(This->png_ptr, &jmpbuf, user_error_fn, user_warning_fn);
1134
1135     ppng_write_end(This->png_ptr, This->info_ptr);
1136
1137     This->frame_committed = TRUE;
1138
1139     LeaveCriticalSection(&This->lock);
1140
1141     return S_OK;
1142 }
1143
1144 static HRESULT WINAPI PngFrameEncode_GetMetadataQueryWriter(IWICBitmapFrameEncode *iface,
1145     IWICMetadataQueryWriter **ppIMetadataQueryWriter)
1146 {
1147     FIXME("(%p, %p): stub\n", iface, ppIMetadataQueryWriter);
1148     return E_NOTIMPL;
1149 }
1150
1151 static const IWICBitmapFrameEncodeVtbl PngEncoder_FrameVtbl = {
1152     PngFrameEncode_QueryInterface,
1153     PngFrameEncode_AddRef,
1154     PngFrameEncode_Release,
1155     PngFrameEncode_Initialize,
1156     PngFrameEncode_SetSize,
1157     PngFrameEncode_SetResolution,
1158     PngFrameEncode_SetPixelFormat,
1159     PngFrameEncode_SetColorContexts,
1160     PngFrameEncode_SetPalette,
1161     PngFrameEncode_SetThumbnail,
1162     PngFrameEncode_WritePixels,
1163     PngFrameEncode_WriteSource,
1164     PngFrameEncode_Commit,
1165     PngFrameEncode_GetMetadataQueryWriter
1166 };
1167
1168 static HRESULT WINAPI PngEncoder_QueryInterface(IWICBitmapEncoder *iface, REFIID iid,
1169     void **ppv)
1170 {
1171     PngEncoder *This = (PngEncoder*)iface;
1172     TRACE("(%p,%s,%p)\n", iface, debugstr_guid(iid), ppv);
1173
1174     if (!ppv) return E_INVALIDARG;
1175
1176     if (IsEqualIID(&IID_IUnknown, iid) ||
1177         IsEqualIID(&IID_IWICBitmapEncoder, iid))
1178     {
1179         *ppv = This;
1180     }
1181     else
1182     {
1183         *ppv = NULL;
1184         return E_NOINTERFACE;
1185     }
1186
1187     IUnknown_AddRef((IUnknown*)*ppv);
1188     return S_OK;
1189 }
1190
1191 static ULONG WINAPI PngEncoder_AddRef(IWICBitmapEncoder *iface)
1192 {
1193     PngEncoder *This = (PngEncoder*)iface;
1194     ULONG ref = InterlockedIncrement(&This->ref);
1195
1196     TRACE("(%p) refcount=%u\n", iface, ref);
1197
1198     return ref;
1199 }
1200
1201 static ULONG WINAPI PngEncoder_Release(IWICBitmapEncoder *iface)
1202 {
1203     PngEncoder *This = (PngEncoder*)iface;
1204     ULONG ref = InterlockedDecrement(&This->ref);
1205
1206     TRACE("(%p) refcount=%u\n", iface, ref);
1207
1208     if (ref == 0)
1209     {
1210         This->lock.DebugInfo->Spare[0] = 0;
1211         DeleteCriticalSection(&This->lock);
1212         if (This->png_ptr)
1213             ppng_destroy_write_struct(&This->png_ptr, &This->info_ptr);
1214         if (This->stream)
1215             IStream_Release(This->stream);
1216         HeapFree(GetProcessHeap(), 0, This);
1217     }
1218
1219     return ref;
1220 }
1221
1222 static void user_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
1223 {
1224     PngEncoder *This = ppng_get_io_ptr(png_ptr);
1225     HRESULT hr;
1226     ULONG byteswritten;
1227
1228     hr = IStream_Write(This->stream, data, length, &byteswritten);
1229     if (FAILED(hr) || byteswritten != length)
1230     {
1231         ppng_error(png_ptr, "failed writing data");
1232     }
1233 }
1234
1235 static void user_flush(png_structp png_ptr)
1236 {
1237 }
1238
1239 static HRESULT WINAPI PngEncoder_Initialize(IWICBitmapEncoder *iface,
1240     IStream *pIStream, WICBitmapEncoderCacheOption cacheOption)
1241 {
1242     PngEncoder *This = (PngEncoder*)iface;
1243     jmp_buf jmpbuf;
1244
1245     TRACE("(%p,%p,%u)\n", iface, pIStream, cacheOption);
1246
1247     EnterCriticalSection(&This->lock);
1248
1249     if (This->png_ptr)
1250     {
1251         LeaveCriticalSection(&This->lock);
1252         return WINCODEC_ERR_WRONGSTATE;
1253     }
1254
1255     /* initialize libpng */
1256     This->png_ptr = ppng_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
1257     if (!This->png_ptr)
1258     {
1259         LeaveCriticalSection(&This->lock);
1260         return E_FAIL;
1261     }
1262
1263     This->info_ptr = ppng_create_info_struct(This->png_ptr);
1264     if (!This->info_ptr)
1265     {
1266         ppng_destroy_write_struct(&This->png_ptr, NULL);
1267         This->png_ptr = NULL;
1268         LeaveCriticalSection(&This->lock);
1269         return E_FAIL;
1270     }
1271
1272     IStream_AddRef(pIStream);
1273     This->stream = pIStream;
1274
1275     /* set up setjmp/longjmp error handling */
1276     if (setjmp(jmpbuf))
1277     {
1278         ppng_destroy_write_struct(&This->png_ptr, &This->info_ptr);
1279         This->png_ptr = NULL;
1280         IStream_Release(This->stream);
1281         This->stream = NULL;
1282         LeaveCriticalSection(&This->lock);
1283         return E_FAIL;
1284     }
1285     ppng_set_error_fn(This->png_ptr, &jmpbuf, user_error_fn, user_warning_fn);
1286
1287     /* set up custom i/o handling */
1288     ppng_set_write_fn(This->png_ptr, This, user_write_data, user_flush);
1289
1290     LeaveCriticalSection(&This->lock);
1291
1292     return S_OK;
1293 }
1294
1295 static HRESULT WINAPI PngEncoder_GetContainerFormat(IWICBitmapEncoder *iface,
1296     GUID *pguidContainerFormat)
1297 {
1298     FIXME("(%p,%s): stub\n", iface, debugstr_guid(pguidContainerFormat));
1299     return E_NOTIMPL;
1300 }
1301
1302 static HRESULT WINAPI PngEncoder_GetEncoderInfo(IWICBitmapEncoder *iface,
1303     IWICBitmapEncoderInfo **ppIEncoderInfo)
1304 {
1305     FIXME("(%p,%p): stub\n", iface, ppIEncoderInfo);
1306     return E_NOTIMPL;
1307 }
1308
1309 static HRESULT WINAPI PngEncoder_SetColorContexts(IWICBitmapEncoder *iface,
1310     UINT cCount, IWICColorContext **ppIColorContext)
1311 {
1312     FIXME("(%p,%u,%p): stub\n", iface, cCount, ppIColorContext);
1313     return E_NOTIMPL;
1314 }
1315
1316 static HRESULT WINAPI PngEncoder_SetPalette(IWICBitmapEncoder *iface, IWICPalette *pIPalette)
1317 {
1318     TRACE("(%p,%p)\n", iface, pIPalette);
1319     return WINCODEC_ERR_UNSUPPORTEDOPERATION;
1320 }
1321
1322 static HRESULT WINAPI PngEncoder_SetThumbnail(IWICBitmapEncoder *iface, IWICBitmapSource *pIThumbnail)
1323 {
1324     TRACE("(%p,%p)\n", iface, pIThumbnail);
1325     return WINCODEC_ERR_UNSUPPORTEDOPERATION;
1326 }
1327
1328 static HRESULT WINAPI PngEncoder_SetPreview(IWICBitmapEncoder *iface, IWICBitmapSource *pIPreview)
1329 {
1330     TRACE("(%p,%p)\n", iface, pIPreview);
1331     return WINCODEC_ERR_UNSUPPORTEDOPERATION;
1332 }
1333
1334 static HRESULT WINAPI PngEncoder_CreateNewFrame(IWICBitmapEncoder *iface,
1335     IWICBitmapFrameEncode **ppIFrameEncode, IPropertyBag2 **ppIEncoderOptions)
1336 {
1337     PngEncoder *This = (PngEncoder*)iface;
1338     HRESULT hr;
1339     TRACE("(%p,%p,%p)\n", iface, ppIFrameEncode, ppIEncoderOptions);
1340
1341     EnterCriticalSection(&This->lock);
1342
1343     if (This->frame_count != 0)
1344     {
1345         LeaveCriticalSection(&This->lock);
1346         return WINCODEC_ERR_UNSUPPORTEDOPERATION;
1347     }
1348
1349     if (!This->stream)
1350     {
1351         LeaveCriticalSection(&This->lock);
1352         return WINCODEC_ERR_NOTINITIALIZED;
1353     }
1354
1355     hr = CreatePropertyBag2(ppIEncoderOptions);
1356     if (FAILED(hr))
1357     {
1358         LeaveCriticalSection(&This->lock);
1359         return hr;
1360     }
1361
1362     This->frame_count = 1;
1363
1364     LeaveCriticalSection(&This->lock);
1365
1366     IWICBitmapEncoder_AddRef(iface);
1367     *ppIFrameEncode = (IWICBitmapFrameEncode*)&This->lpFrameVtbl;
1368
1369     return S_OK;
1370 }
1371
1372 static HRESULT WINAPI PngEncoder_Commit(IWICBitmapEncoder *iface)
1373 {
1374     PngEncoder *This = (PngEncoder*)iface;
1375     TRACE("(%p)\n", iface);
1376
1377     EnterCriticalSection(&This->lock);
1378
1379     if (!This->frame_committed || This->committed)
1380     {
1381         LeaveCriticalSection(&This->lock);
1382         return WINCODEC_ERR_WRONGSTATE;
1383     }
1384
1385     This->committed = TRUE;
1386
1387     EnterCriticalSection(&This->lock);
1388
1389     return S_OK;
1390 }
1391
1392 static HRESULT WINAPI PngEncoder_GetMetadataQueryWriter(IWICBitmapEncoder *iface,
1393     IWICMetadataQueryWriter **ppIMetadataQueryWriter)
1394 {
1395     FIXME("(%p,%p): stub\n", iface, ppIMetadataQueryWriter);
1396     return E_NOTIMPL;
1397 }
1398
1399 static const IWICBitmapEncoderVtbl PngEncoder_Vtbl = {
1400     PngEncoder_QueryInterface,
1401     PngEncoder_AddRef,
1402     PngEncoder_Release,
1403     PngEncoder_Initialize,
1404     PngEncoder_GetContainerFormat,
1405     PngEncoder_GetEncoderInfo,
1406     PngEncoder_SetColorContexts,
1407     PngEncoder_SetPalette,
1408     PngEncoder_SetThumbnail,
1409     PngEncoder_SetPreview,
1410     PngEncoder_CreateNewFrame,
1411     PngEncoder_Commit,
1412     PngEncoder_GetMetadataQueryWriter
1413 };
1414
1415 HRESULT PngEncoder_CreateInstance(IUnknown *pUnkOuter, REFIID iid, void** ppv)
1416 {
1417     PngEncoder *This;
1418     HRESULT ret;
1419
1420     TRACE("(%p,%s,%p)\n", pUnkOuter, debugstr_guid(iid), ppv);
1421
1422     *ppv = NULL;
1423
1424     if (pUnkOuter) return CLASS_E_NOAGGREGATION;
1425
1426     if (!libpng_handle && !load_libpng())
1427     {
1428         ERR("Failed writing PNG because unable to find %s\n",SONAME_LIBPNG);
1429         return E_FAIL;
1430     }
1431
1432     This = HeapAlloc(GetProcessHeap(), 0, sizeof(PngEncoder));
1433     if (!This) return E_OUTOFMEMORY;
1434
1435     This->lpVtbl = &PngEncoder_Vtbl;
1436     This->lpFrameVtbl = &PngEncoder_FrameVtbl;
1437     This->ref = 1;
1438     This->png_ptr = NULL;
1439     This->info_ptr = NULL;
1440     This->stream = NULL;
1441     This->frame_count = 0;
1442     This->frame_initialized = FALSE;
1443     This->format = NULL;
1444     This->info_written = FALSE;
1445     This->width = 0;
1446     This->height = 0;
1447     This->xres = 0.0;
1448     This->yres = 0.0;
1449     This->lines_written = 0;
1450     This->frame_committed = FALSE;
1451     This->committed = FALSE;
1452     InitializeCriticalSection(&This->lock);
1453     This->lock.DebugInfo->Spare[0] = (DWORD_PTR)(__FILE__ ": PngEncoder.lock");
1454
1455     ret = IUnknown_QueryInterface((IUnknown*)This, iid, ppv);
1456     IUnknown_Release((IUnknown*)This);
1457
1458     return ret;
1459 }
1460
1461 #else /* !HAVE_PNG_H */
1462
1463 HRESULT PngDecoder_CreateInstance(IUnknown *pUnkOuter, REFIID iid, void** ppv)
1464 {
1465     ERR("Trying to load PNG picture, but PNG support is not compiled in.\n");
1466     return E_FAIL;
1467 }
1468
1469 HRESULT PngEncoder_CreateInstance(IUnknown *pUnkOuter, REFIID iid, void** ppv)
1470 {
1471     ERR("Trying to save PNG picture, but PNG support is not compiled in.\n");
1472     return E_FAIL;
1473 }
1474
1475 #endif