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1 // Copyright 2014 PDFium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
6 
7 #include <algorithm>
8 #include <limits>
9 #include <memory>
10 #include <utility>
11 #include <vector>
12 
13 #include "core/fpdfapi/page/cpdf_colorspace.h"
14 #include "core/fxcodec/codec/ccodec_jpxmodule.h"
15 #include "core/fxcodec/codec/cjpx_decoder.h"
16 #include "core/fxcrt/fx_memory.h"
17 #include "core/fxcrt/fx_safe_types.h"
18 #include "third_party/base/ptr_util.h"
19 #include "third_party/libopenjpeg20/openjpeg.h"
20 #include "third_party/libopenjpeg20/opj_malloc.h"
21 
22 namespace {
23 
fx_ignore_callback(const char * msg,void * client_data)24 void fx_ignore_callback(const char* msg, void* client_data) {}
25 
fx_opj_stream_create_memory_stream(DecodeData * data,OPJ_SIZE_T p_size,OPJ_BOOL p_is_read_stream)26 opj_stream_t* fx_opj_stream_create_memory_stream(DecodeData* data,
27                                                  OPJ_SIZE_T p_size,
28                                                  OPJ_BOOL p_is_read_stream) {
29   if (!data || !data->src_data || data->src_size <= 0)
30     return nullptr;
31 
32   opj_stream_t* stream = opj_stream_create(p_size, p_is_read_stream);
33   if (!stream)
34     return nullptr;
35 
36   opj_stream_set_user_data(stream, data, nullptr);
37   opj_stream_set_user_data_length(stream, data->src_size);
38   opj_stream_set_read_function(stream, opj_read_from_memory);
39   opj_stream_set_skip_function(stream, opj_skip_from_memory);
40   opj_stream_set_seek_function(stream, opj_seek_from_memory);
41   return stream;
42 }
43 
sycc_to_rgb(int offset,int upb,int y,int cb,int cr,int * out_r,int * out_g,int * out_b)44 void sycc_to_rgb(int offset,
45                  int upb,
46                  int y,
47                  int cb,
48                  int cr,
49                  int* out_r,
50                  int* out_g,
51                  int* out_b) {
52   cb -= offset;
53   cr -= offset;
54   *out_r = pdfium::clamp(y + static_cast<int>(1.402 * cr), 0, upb);
55   *out_g = pdfium::clamp(y - static_cast<int>(0.344 * cb + 0.714 * cr), 0, upb);
56   *out_b = pdfium::clamp(y + static_cast<int>(1.772 * cb), 0, upb);
57 }
58 
sycc444_to_rgb(opj_image_t * img)59 void sycc444_to_rgb(opj_image_t* img) {
60   int prec = img->comps[0].prec;
61   // If we shift 31 we're going to go negative, then things go bad.
62   if (prec > 30)
63     return;
64   int offset = 1 << (prec - 1);
65   int upb = (1 << prec) - 1;
66   OPJ_UINT32 maxw =
67       std::min({img->comps[0].w, img->comps[1].w, img->comps[2].w});
68   OPJ_UINT32 maxh =
69       std::min({img->comps[0].h, img->comps[1].h, img->comps[2].h});
70   FX_SAFE_SIZE_T max_size = maxw;
71   max_size *= maxh;
72   max_size *= sizeof(int);
73   if (!max_size.IsValid())
74     return;
75 
76   const int* y = img->comps[0].data;
77   const int* cb = img->comps[1].data;
78   const int* cr = img->comps[2].data;
79   if (!y || !cb || !cr)
80     return;
81 
82   int* r = static_cast<int*>(opj_image_data_alloc(max_size.ValueOrDie()));
83   int* g = static_cast<int*>(opj_image_data_alloc(max_size.ValueOrDie()));
84   int* b = static_cast<int*>(opj_image_data_alloc(max_size.ValueOrDie()));
85   int* d0 = r;
86   int* d1 = g;
87   int* d2 = b;
88   max_size /= sizeof(int);
89   for (size_t i = 0; i < max_size.ValueOrDie(); ++i) {
90     sycc_to_rgb(offset, upb, *y++, *cb++, *cr++, r++, g++, b++);
91   }
92   opj_image_data_free(img->comps[0].data);
93   opj_image_data_free(img->comps[1].data);
94   opj_image_data_free(img->comps[2].data);
95   img->comps[0].data = d0;
96   img->comps[1].data = d1;
97   img->comps[2].data = d2;
98 }
99 
sycc420_422_size_is_valid(opj_image_t * img)100 bool sycc420_422_size_is_valid(opj_image_t* img) {
101   return img && img->comps[0].w != std::numeric_limits<OPJ_UINT32>::max() &&
102          (img->comps[0].w + 1) / 2 == img->comps[1].w &&
103          img->comps[1].w == img->comps[2].w &&
104          img->comps[1].h == img->comps[2].h;
105 }
106 
sycc420_size_is_valid(opj_image_t * img)107 bool sycc420_size_is_valid(opj_image_t* img) {
108   return sycc420_422_size_is_valid(img) &&
109          img->comps[0].h != std::numeric_limits<OPJ_UINT32>::max() &&
110          (img->comps[0].h + 1) / 2 == img->comps[1].h;
111 }
112 
sycc422_size_is_valid(opj_image_t * img)113 bool sycc422_size_is_valid(opj_image_t* img) {
114   return sycc420_422_size_is_valid(img) && img->comps[0].h == img->comps[1].h;
115 }
116 
sycc422_to_rgb(opj_image_t * img)117 void sycc422_to_rgb(opj_image_t* img) {
118   if (!sycc422_size_is_valid(img))
119     return;
120 
121   int prec = img->comps[0].prec;
122   if (prec <= 0 || prec >= 32)
123     return;
124 
125   int offset = 1 << (prec - 1);
126   int upb = (1 << prec) - 1;
127   OPJ_UINT32 maxw = img->comps[0].w;
128   OPJ_UINT32 maxh = img->comps[0].h;
129   FX_SAFE_SIZE_T max_size = maxw;
130   max_size *= maxh;
131   max_size *= sizeof(int);
132   if (!max_size.IsValid())
133     return;
134 
135   const int* y = img->comps[0].data;
136   const int* cb = img->comps[1].data;
137   const int* cr = img->comps[2].data;
138   if (!y || !cb || !cr)
139     return;
140 
141   int* r = static_cast<int*>(opj_image_data_alloc(max_size.ValueOrDie()));
142   int* g = static_cast<int*>(opj_image_data_alloc(max_size.ValueOrDie()));
143   int* b = static_cast<int*>(opj_image_data_alloc(max_size.ValueOrDie()));
144   int* d0 = r;
145   int* d1 = g;
146   int* d2 = b;
147   for (uint32_t i = 0; i < maxh; ++i) {
148     OPJ_UINT32 j;
149     for (j = 0; j < (maxw & ~static_cast<OPJ_UINT32>(1)); j += 2) {
150       sycc_to_rgb(offset, upb, *y++, *cb, *cr, r++, g++, b++);
151       sycc_to_rgb(offset, upb, *y++, *cb++, *cr++, r++, g++, b++);
152     }
153     if (j < maxw) {
154       sycc_to_rgb(offset, upb, *y++, *cb++, *cr++, r++, g++, b++);
155     }
156   }
157   opj_image_data_free(img->comps[0].data);
158   opj_image_data_free(img->comps[1].data);
159   opj_image_data_free(img->comps[2].data);
160   img->comps[0].data = d0;
161   img->comps[1].data = d1;
162   img->comps[2].data = d2;
163   img->comps[1].w = maxw;
164   img->comps[1].h = maxh;
165   img->comps[2].w = maxw;
166   img->comps[2].h = maxh;
167   img->comps[1].dx = img->comps[0].dx;
168   img->comps[2].dx = img->comps[0].dx;
169   img->comps[1].dy = img->comps[0].dy;
170   img->comps[2].dy = img->comps[0].dy;
171 }
172 
sycc420_must_extend_cbcr(OPJ_UINT32 y,OPJ_UINT32 cbcr)173 bool sycc420_must_extend_cbcr(OPJ_UINT32 y, OPJ_UINT32 cbcr) {
174   return (y & 1) && (cbcr == y / 2);
175 }
176 
is_sycc420(const opj_image_t * img)177 bool is_sycc420(const opj_image_t* img) {
178   return img->comps[0].dx == 1 && img->comps[0].dy == 1 &&
179          img->comps[1].dx == 2 && img->comps[1].dy == 2 &&
180          img->comps[2].dx == 2 && img->comps[2].dy == 2;
181 }
182 
is_sycc422(const opj_image_t * img)183 bool is_sycc422(const opj_image_t* img) {
184   return img->comps[0].dx == 1 && img->comps[0].dy == 1 &&
185          img->comps[1].dx == 2 && img->comps[1].dy == 1 &&
186          img->comps[2].dx == 2 && img->comps[2].dy == 1;
187 }
188 
is_sycc444(const opj_image_t * img)189 bool is_sycc444(const opj_image_t* img) {
190   return img->comps[0].dx == 1 && img->comps[0].dy == 1 &&
191          img->comps[1].dx == 1 && img->comps[1].dy == 1 &&
192          img->comps[2].dx == 1 && img->comps[2].dy == 1;
193 }
194 
color_sycc_to_rgb(opj_image_t * img)195 void color_sycc_to_rgb(opj_image_t* img) {
196   if (img->numcomps < 3) {
197     img->color_space = OPJ_CLRSPC_GRAY;
198     return;
199   }
200   if (is_sycc420(img))
201     sycc420_to_rgb(img);
202   else if (is_sycc422(img))
203     sycc422_to_rgb(img);
204   else if (is_sycc444(img))
205     sycc444_to_rgb(img);
206   else
207     return;
208 
209   img->color_space = OPJ_CLRSPC_SRGB;
210 }
211 
212 }  // namespace
213 
opj_read_from_memory(void * p_buffer,OPJ_SIZE_T nb_bytes,void * p_user_data)214 OPJ_SIZE_T opj_read_from_memory(void* p_buffer,
215                                 OPJ_SIZE_T nb_bytes,
216                                 void* p_user_data) {
217   DecodeData* srcData = static_cast<DecodeData*>(p_user_data);
218   if (!srcData || !srcData->src_data || srcData->src_size == 0)
219     return static_cast<OPJ_SIZE_T>(-1);
220 
221   // Reads at EOF return an error code.
222   if (srcData->offset >= srcData->src_size)
223     return static_cast<OPJ_SIZE_T>(-1);
224 
225   OPJ_SIZE_T bufferLength = srcData->src_size - srcData->offset;
226   OPJ_SIZE_T readlength = nb_bytes < bufferLength ? nb_bytes : bufferLength;
227   memcpy(p_buffer, &srcData->src_data[srcData->offset], readlength);
228   srcData->offset += readlength;
229   return readlength;
230 }
231 
opj_skip_from_memory(OPJ_OFF_T nb_bytes,void * p_user_data)232 OPJ_OFF_T opj_skip_from_memory(OPJ_OFF_T nb_bytes, void* p_user_data) {
233   DecodeData* srcData = static_cast<DecodeData*>(p_user_data);
234   if (!srcData || !srcData->src_data || srcData->src_size == 0)
235     return static_cast<OPJ_OFF_T>(-1);
236 
237   // Offsets are signed and may indicate a negative skip. Do not support this
238   // because of the strange return convention where either bytes skipped or
239   // -1 is returned. Following that convention, a successful relative seek of
240   // -1 bytes would be required to to give the same result as the error case.
241   if (nb_bytes < 0)
242     return static_cast<OPJ_OFF_T>(-1);
243 
244   // FIXME: use std::make_unsigned<OPJ_OFF_T>::type once c++11 lib is OK'd.
245   uint64_t unsignedNbBytes = static_cast<uint64_t>(nb_bytes);
246   // Additionally, the offset may take us beyond the range of a size_t (e.g.
247   // 32-bit platforms). If so, just clamp at EOF.
248   if (unsignedNbBytes >
249       std::numeric_limits<OPJ_SIZE_T>::max() - srcData->offset) {
250     srcData->offset = srcData->src_size;
251   } else {
252     OPJ_SIZE_T checkedNbBytes = static_cast<OPJ_SIZE_T>(unsignedNbBytes);
253     // Otherwise, mimic fseek() semantics to always succeed, even past EOF,
254     // clamping at EOF.  We can get away with this since we don't actually
255     // provide negative relative skips from beyond EOF back to inside the
256     // data, which would be the only reason to need to know exactly how far
257     // beyond EOF we are.
258     srcData->offset =
259         std::min(srcData->offset + checkedNbBytes, srcData->src_size);
260   }
261   return nb_bytes;
262 }
263 
opj_seek_from_memory(OPJ_OFF_T nb_bytes,void * p_user_data)264 OPJ_BOOL opj_seek_from_memory(OPJ_OFF_T nb_bytes, void* p_user_data) {
265   DecodeData* srcData = static_cast<DecodeData*>(p_user_data);
266   if (!srcData || !srcData->src_data || srcData->src_size == 0)
267     return OPJ_FALSE;
268 
269   // Offsets are signed and may indicate a negative position, which would
270   // be before the start of the file. Do not support this.
271   if (nb_bytes < 0)
272     return OPJ_FALSE;
273 
274   // FIXME: use std::make_unsigned<OPJ_OFF_T>::type once c++11 lib is OK'd.
275   uint64_t unsignedNbBytes = static_cast<uint64_t>(nb_bytes);
276   // Additionally, the offset may take us beyond the range of a size_t (e.g.
277   // 32-bit platforms). If so, just clamp at EOF.
278   if (unsignedNbBytes > std::numeric_limits<OPJ_SIZE_T>::max()) {
279     srcData->offset = srcData->src_size;
280   } else {
281     OPJ_SIZE_T checkedNbBytes = static_cast<OPJ_SIZE_T>(nb_bytes);
282     // Otherwise, mimic fseek() semantics to always succeed, even past EOF,
283     // again clamping at EOF.
284     srcData->offset = std::min(checkedNbBytes, srcData->src_size);
285   }
286   return OPJ_TRUE;
287 }
288 
sycc420_to_rgb(opj_image_t * img)289 void sycc420_to_rgb(opj_image_t* img) {
290   if (!sycc420_size_is_valid(img))
291     return;
292 
293   OPJ_UINT32 prec = img->comps[0].prec;
294   if (!prec)
295     return;
296 
297   OPJ_UINT32 offset = 1 << (prec - 1);
298   OPJ_UINT32 upb = (1 << prec) - 1;
299   OPJ_UINT32 yw = img->comps[0].w;
300   OPJ_UINT32 yh = img->comps[0].h;
301   OPJ_UINT32 cbw = img->comps[1].w;
302   OPJ_UINT32 cbh = img->comps[1].h;
303   OPJ_UINT32 crw = img->comps[2].w;
304   bool extw = sycc420_must_extend_cbcr(yw, cbw);
305   bool exth = sycc420_must_extend_cbcr(yh, cbh);
306   FX_SAFE_UINT32 safeSize = yw;
307   safeSize *= yh;
308   safeSize *= sizeof(int);
309   if (!safeSize.IsValid())
310     return;
311 
312   int* r = static_cast<int*>(opj_image_data_alloc(safeSize.ValueOrDie()));
313   int* g = static_cast<int*>(opj_image_data_alloc(safeSize.ValueOrDie()));
314   int* b = static_cast<int*>(opj_image_data_alloc(safeSize.ValueOrDie()));
315   int* d0 = r;
316   int* d1 = g;
317   int* d2 = b;
318   const int* y = img->comps[0].data;
319   const int* cb = img->comps[1].data;
320   const int* cr = img->comps[2].data;
321   if (!y || !cb || !cr)
322     return;
323 
324   const int* ny = nullptr;
325   int* nr = nullptr;
326   int* ng = nullptr;
327   int* nb = nullptr;
328   OPJ_UINT32 i = 0;
329   OPJ_UINT32 j = 0;
330   for (i = 0; i < (yh & ~(OPJ_UINT32)1); i += 2) {
331     ny = y + yw;
332     nr = r + yw;
333     ng = g + yw;
334     nb = b + yw;
335     for (j = 0; j < (yw & ~(OPJ_UINT32)1); j += 2) {
336       sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
337       ++y;
338       ++r;
339       ++g;
340       ++b;
341       sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
342       ++y;
343       ++r;
344       ++g;
345       ++b;
346       sycc_to_rgb(offset, upb, *ny, *cb, *cr, nr, ng, nb);
347       ++ny;
348       ++nr;
349       ++ng;
350       ++nb;
351       sycc_to_rgb(offset, upb, *ny, *cb, *cr, nr, ng, nb);
352       ++ny;
353       ++nr;
354       ++ng;
355       ++nb;
356       ++cb;
357       ++cr;
358     }
359     if (j < yw) {
360       if (extw) {
361         --cb;
362         --cr;
363       }
364       sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
365       ++y;
366       ++r;
367       ++g;
368       ++b;
369       sycc_to_rgb(offset, upb, *ny, *cb, *cr, nr, ng, nb);
370       ++ny;
371       ++nr;
372       ++ng;
373       ++nb;
374       ++cb;
375       ++cr;
376     }
377     y += yw;
378     r += yw;
379     g += yw;
380     b += yw;
381   }
382   if (i < yh) {
383     if (exth) {
384       cb -= cbw;
385       cr -= crw;
386     }
387     for (j = 0; j < (yw & ~(OPJ_UINT32)1); j += 2) {
388       sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
389       ++y;
390       ++r;
391       ++g;
392       ++b;
393       sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
394       ++y;
395       ++r;
396       ++g;
397       ++b;
398       ++cb;
399       ++cr;
400     }
401     if (j < yw) {
402       if (extw) {
403         --cb;
404         --cr;
405       }
406       sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
407     }
408   }
409 
410   opj_image_data_free(img->comps[0].data);
411   opj_image_data_free(img->comps[1].data);
412   opj_image_data_free(img->comps[2].data);
413   img->comps[0].data = d0;
414   img->comps[1].data = d1;
415   img->comps[2].data = d2;
416   img->comps[1].w = yw;
417   img->comps[1].h = yh;
418   img->comps[2].w = yw;
419   img->comps[2].h = yh;
420   img->comps[1].w = yw;
421   img->comps[1].h = yh;
422   img->comps[2].w = yw;
423   img->comps[2].h = yh;
424   img->comps[1].dx = img->comps[0].dx;
425   img->comps[2].dx = img->comps[0].dx;
426   img->comps[1].dy = img->comps[0].dy;
427   img->comps[2].dy = img->comps[0].dy;
428 }
429 
CJPX_Decoder(CPDF_ColorSpace * cs)430 CJPX_Decoder::CJPX_Decoder(CPDF_ColorSpace* cs)
431     : m_Image(nullptr),
432       m_Codec(nullptr),
433       m_DecodeData(nullptr),
434       m_Stream(nullptr),
435       m_ColorSpace(cs) {}
436 
~CJPX_Decoder()437 CJPX_Decoder::~CJPX_Decoder() {
438   if (m_Codec)
439     opj_destroy_codec(m_Codec);
440   if (m_Stream)
441     opj_stream_destroy(m_Stream);
442   if (m_Image)
443     opj_image_destroy(m_Image);
444 }
445 
Init(const unsigned char * src_data,uint32_t src_size)446 bool CJPX_Decoder::Init(const unsigned char* src_data, uint32_t src_size) {
447   static const unsigned char szJP2Header[] = {
448       0x00, 0x00, 0x00, 0x0c, 0x6a, 0x50, 0x20, 0x20, 0x0d, 0x0a, 0x87, 0x0a};
449   if (!src_data || src_size < sizeof(szJP2Header))
450     return false;
451 
452   m_Image = nullptr;
453   m_SrcData = src_data;
454   m_SrcSize = src_size;
455   m_DecodeData = pdfium::MakeUnique<DecodeData>(
456       const_cast<unsigned char*>(src_data), src_size);
457   m_Stream = fx_opj_stream_create_memory_stream(
458       m_DecodeData.get(), static_cast<unsigned int>(OPJ_J2K_STREAM_CHUNK_SIZE),
459       1);
460   if (!m_Stream)
461     return false;
462 
463   opj_set_default_decoder_parameters(&m_Parameters);
464   m_Parameters.decod_format = 0;
465   m_Parameters.cod_format = 3;
466   if (memcmp(m_SrcData, szJP2Header, sizeof(szJP2Header)) == 0) {
467     m_Codec = opj_create_decompress(OPJ_CODEC_JP2);
468     m_Parameters.decod_format = 1;
469   } else {
470     m_Codec = opj_create_decompress(OPJ_CODEC_J2K);
471   }
472   if (!m_Codec)
473     return false;
474 
475   if (m_ColorSpace && m_ColorSpace->GetFamily() == PDFCS_INDEXED)
476     m_Parameters.flags |= OPJ_DPARAMETERS_IGNORE_PCLR_CMAP_CDEF_FLAG;
477   opj_set_info_handler(m_Codec, fx_ignore_callback, nullptr);
478   opj_set_warning_handler(m_Codec, fx_ignore_callback, nullptr);
479   opj_set_error_handler(m_Codec, fx_ignore_callback, nullptr);
480   if (!opj_setup_decoder(m_Codec, &m_Parameters))
481     return false;
482 
483   if (!opj_read_header(m_Stream, m_Codec, &m_Image)) {
484     m_Image = nullptr;
485     return false;
486   }
487   m_Image->pdfium_use_colorspace = !!m_ColorSpace;
488 
489   if (!m_Parameters.nb_tile_to_decode) {
490     if (!opj_set_decode_area(m_Codec, m_Image, m_Parameters.DA_x0,
491                              m_Parameters.DA_y0, m_Parameters.DA_x1,
492                              m_Parameters.DA_y1)) {
493       opj_image_destroy(m_Image);
494       m_Image = nullptr;
495       return false;
496     }
497     if (!(opj_decode(m_Codec, m_Stream, m_Image) &&
498           opj_end_decompress(m_Codec, m_Stream))) {
499       opj_image_destroy(m_Image);
500       m_Image = nullptr;
501       return false;
502     }
503   } else if (!opj_get_decoded_tile(m_Codec, m_Stream, m_Image,
504                                    m_Parameters.tile_index)) {
505     return false;
506   }
507 
508   opj_stream_destroy(m_Stream);
509   m_Stream = nullptr;
510   if (m_Image->color_space != OPJ_CLRSPC_SYCC && m_Image->numcomps == 3 &&
511       m_Image->comps[0].dx == m_Image->comps[0].dy &&
512       m_Image->comps[1].dx != 1) {
513     m_Image->color_space = OPJ_CLRSPC_SYCC;
514   } else if (m_Image->numcomps <= 2) {
515     m_Image->color_space = OPJ_CLRSPC_GRAY;
516   }
517   if (m_Image->color_space == OPJ_CLRSPC_SYCC)
518     color_sycc_to_rgb(m_Image);
519 
520   if (m_Image->icc_profile_buf) {
521     // TODO(palmer): Using |opj_free| here resolves the crash described in
522     // https://crbug.com/737033, but ultimately we need to harmonize the
523     // memory allocation strategy across OpenJPEG and its PDFium callers.
524     opj_free(m_Image->icc_profile_buf);
525     m_Image->icc_profile_buf = nullptr;
526     m_Image->icc_profile_len = 0;
527   }
528 
529   return true;
530 }
531 
GetInfo(uint32_t * width,uint32_t * height,uint32_t * components)532 void CJPX_Decoder::GetInfo(uint32_t* width,
533                            uint32_t* height,
534                            uint32_t* components) {
535   *width = m_Image->x1;
536   *height = m_Image->y1;
537   *components = m_Image->numcomps;
538 }
539 
Decode(uint8_t * dest_buf,int pitch,const std::vector<uint8_t> & offsets)540 bool CJPX_Decoder::Decode(uint8_t* dest_buf,
541                           int pitch,
542                           const std::vector<uint8_t>& offsets) {
543   if (m_Image->comps[0].w != m_Image->x1 || m_Image->comps[0].h != m_Image->y1)
544     return false;
545 
546   if (pitch<static_cast<int>(m_Image->comps[0].w * 8 * m_Image->numcomps + 31)>>
547       5 << 2) {
548     return false;
549   }
550 
551   memset(dest_buf, 0xff, m_Image->y1 * pitch);
552   std::vector<uint8_t*> channel_bufs(m_Image->numcomps);
553   std::vector<int> adjust_comps(m_Image->numcomps);
554   for (uint32_t i = 0; i < m_Image->numcomps; i++) {
555     channel_bufs[i] = dest_buf + offsets[i];
556     adjust_comps[i] = m_Image->comps[i].prec - 8;
557     if (i > 0) {
558       if (m_Image->comps[i].dx != m_Image->comps[i - 1].dx ||
559           m_Image->comps[i].dy != m_Image->comps[i - 1].dy ||
560           m_Image->comps[i].prec != m_Image->comps[i - 1].prec) {
561         return false;
562       }
563     }
564   }
565   int width = m_Image->comps[0].w;
566   int height = m_Image->comps[0].h;
567   for (uint32_t channel = 0; channel < m_Image->numcomps; ++channel) {
568     uint8_t* pChannel = channel_bufs[channel];
569     if (adjust_comps[channel] < 0) {
570       for (int row = 0; row < height; ++row) {
571         uint8_t* pScanline = pChannel + row * pitch;
572         for (int col = 0; col < width; ++col) {
573           uint8_t* pPixel = pScanline + col * m_Image->numcomps;
574           if (!m_Image->comps[channel].data)
575             continue;
576 
577           int src = m_Image->comps[channel].data[row * width + col];
578           src += m_Image->comps[channel].sgnd
579                      ? 1 << (m_Image->comps[channel].prec - 1)
580                      : 0;
581           if (adjust_comps[channel] > 0) {
582             *pPixel = 0;
583           } else {
584             *pPixel = static_cast<uint8_t>(src << -adjust_comps[channel]);
585           }
586         }
587       }
588     } else {
589       for (int row = 0; row < height; ++row) {
590         uint8_t* pScanline = pChannel + row * pitch;
591         for (int col = 0; col < width; ++col) {
592           uint8_t* pPixel = pScanline + col * m_Image->numcomps;
593           if (!m_Image->comps[channel].data)
594             continue;
595 
596           int src = m_Image->comps[channel].data[row * width + col];
597           src += m_Image->comps[channel].sgnd
598                      ? 1 << (m_Image->comps[channel].prec - 1)
599                      : 0;
600           if (adjust_comps[channel] - 1 < 0) {
601             *pPixel = static_cast<uint8_t>((src >> adjust_comps[channel]));
602           } else {
603             int tmpPixel = (src >> adjust_comps[channel]) +
604                            ((src >> (adjust_comps[channel] - 1)) % 2);
605             tmpPixel = pdfium::clamp(tmpPixel, 0, 255);
606             *pPixel = static_cast<uint8_t>(tmpPixel);
607           }
608         }
609       }
610     }
611   }
612   return true;
613 }
614 
CCodec_JpxModule()615 CCodec_JpxModule::CCodec_JpxModule() {}
616 
~CCodec_JpxModule()617 CCodec_JpxModule::~CCodec_JpxModule() {}
618 
CreateDecoder(const uint8_t * src_buf,uint32_t src_size,CPDF_ColorSpace * cs)619 std::unique_ptr<CJPX_Decoder> CCodec_JpxModule::CreateDecoder(
620     const uint8_t* src_buf,
621     uint32_t src_size,
622     CPDF_ColorSpace* cs) {
623   auto decoder = pdfium::MakeUnique<CJPX_Decoder>(cs);
624   return decoder->Init(src_buf, src_size) ? std::move(decoder) : nullptr;
625 }
626 
GetImageInfo(CJPX_Decoder * pDecoder,uint32_t * width,uint32_t * height,uint32_t * components)627 void CCodec_JpxModule::GetImageInfo(CJPX_Decoder* pDecoder,
628                                     uint32_t* width,
629                                     uint32_t* height,
630                                     uint32_t* components) {
631   pDecoder->GetInfo(width, height, components);
632 }
633 
Decode(CJPX_Decoder * pDecoder,uint8_t * dest_data,int pitch,const std::vector<uint8_t> & offsets)634 bool CCodec_JpxModule::Decode(CJPX_Decoder* pDecoder,
635                               uint8_t* dest_data,
636                               int pitch,
637                               const std::vector<uint8_t>& offsets) {
638   return pDecoder->Decode(dest_data, pitch, offsets);
639 }
640