APIs and tests for retrieving raw/decoded data from image objects
Added FPDFImageObj_GetImageDataDecoded() for retrieving the uncompressed
data of an image, and FPDFImageObj_GetImageDataRaw() for retrieving the
raw data of an image.
* Refactored out DecodeStreamMaybeCopyAndReturnLength(), which is
used to decode both attachment data and image data.
* Within DecodeStreamMaybeCopyAndReturnLength(), used a different
decoder function which takes care of multiple filters if exist. As
a result, CPDF_StreamParser::DecodeInlineStream() which was made
static previously is now moved back into namespace.
Bug=pdfium:677
Change-Id: I22a22c99acaca98ef8c15f88911f2646a2c854d5
Reviewed-on: https://pdfium-review.googlesource.com/9811
Commit-Queue: Jane Liu <janeliulwq@google.com>
Reviewed-by: Lei Zhang <thestig@chromium.org>
diff --git a/fpdfsdk/fpdfattachment.cpp b/fpdfsdk/fpdfattachment.cpp
index 0cb623f..5bdb3bd 100644
--- a/fpdfsdk/fpdfattachment.cpp
+++ b/fpdfsdk/fpdfattachment.cpp
@@ -8,7 +8,6 @@
#include <utility>
#include "core/fdrm/crypto/fx_crypt.h"
-#include "core/fpdfapi/page/cpdf_streamparser.h"
#include "core/fpdfapi/parser/cpdf_array.h"
#include "core/fpdfapi/parser/cpdf_document.h"
#include "core/fpdfapi/parser/cpdf_name.h"
@@ -273,26 +272,5 @@
if (!pFileStream)
return 0;
- uint8_t* data = pFileStream->GetRawData();
- uint32_t len = pFileStream->GetRawSize();
- CPDF_Dictionary* pFileDict = pFileStream->GetDict();
- if (!pFileDict || pFileDict->GetStringFor("Filter").IsEmpty()) {
- if (buffer && buflen >= len)
- memcpy(buffer, data, len);
-
- return len;
- }
-
- // Decode the stream if a stream filter is specified.
- uint8_t* decodedData = nullptr;
- uint32_t decodedLen = 0;
- CPDF_StreamParser::DecodeInlineStream(
- data, len, pFileDict->GetIntegerFor("Width"),
- pFileDict->GetIntegerFor("Height"), pFileDict->GetStringFor("Filter"),
- pFileDict->GetDictFor("DecodeParms"), &decodedData, &decodedLen);
- if (buffer && buflen >= decodedLen)
- memcpy(buffer, decodedData, decodedLen);
-
- FX_Free(decodedData);
- return decodedLen;
+ return DecodeStreamMaybeCopyAndReturnLength(pFileStream, buffer, buflen);
}
diff --git a/fpdfsdk/fpdfedit_embeddertest.cpp b/fpdfsdk/fpdfedit_embeddertest.cpp
index dcaeb94..f1bbb87 100644
--- a/fpdfsdk/fpdfedit_embeddertest.cpp
+++ b/fpdfsdk/fpdfedit_embeddertest.cpp
@@ -5,6 +5,7 @@
#include <memory>
#include <string>
#include <utility>
+#include <vector>
#include "core/fpdfapi/font/cpdf_font.h"
#include "core/fpdfapi/page/cpdf_page.h"
@@ -979,3 +980,53 @@
FPDFBitmap_Destroy(bitmap);
UnloadPage(page);
}
+
+TEST_F(FPDFEditEmbeddertest, GetImageData) {
+ EXPECT_TRUE(OpenDocument("embedded_images.pdf"));
+ FPDF_PAGE page = LoadPage(0);
+ ASSERT_TRUE(page);
+ ASSERT_EQ(39, FPDFPage_CountObject(page));
+
+ // Retrieve an image object with flate-encoded data stream.
+ FPDF_PAGEOBJECT obj = FPDFPage_GetObject(page, 33);
+ ASSERT_EQ(FPDF_PAGEOBJ_IMAGE, FPDFPageObj_GetType(obj));
+
+ // Check that the raw image data has the correct length and hash value.
+ unsigned long len = FPDFImageObj_GetImageDataRaw(obj, nullptr, 0);
+ std::vector<char> buf(len);
+ EXPECT_EQ(4091u, FPDFImageObj_GetImageDataRaw(obj, buf.data(), len));
+ EXPECT_EQ("f73802327d2e88e890f653961bcda81a",
+ GenerateMD5Base16(reinterpret_cast<uint8_t*>(buf.data()), len));
+
+ // Check that the decoded image data has the correct length and hash value.
+ len = FPDFImageObj_GetImageDataDecoded(obj, nullptr, 0);
+ buf.clear();
+ buf.resize(len);
+ EXPECT_EQ(28776u, FPDFImageObj_GetImageDataDecoded(obj, buf.data(), len));
+ EXPECT_EQ("cb3637934bb3b95a6e4ae1ea9eb9e56e",
+ GenerateMD5Base16(reinterpret_cast<uint8_t*>(buf.data()), len));
+
+ // Retrieve an image obejct with DCTDecode-encoded data stream.
+ obj = FPDFPage_GetObject(page, 37);
+ ASSERT_EQ(FPDF_PAGEOBJ_IMAGE, FPDFPageObj_GetType(obj));
+
+ // Check that the raw image data has the correct length and hash value.
+ len = FPDFImageObj_GetImageDataRaw(obj, nullptr, 0);
+ buf.clear();
+ buf.resize(len);
+ EXPECT_EQ(4370u, FPDFImageObj_GetImageDataRaw(obj, buf.data(), len));
+ EXPECT_EQ("6aae1f3710335023a9e12191be66b64b",
+ GenerateMD5Base16(reinterpret_cast<uint8_t*>(buf.data()), len));
+
+ // Check that the decoded image data has the correct length and hash value,
+ // which should be the same as those of the raw data, since this image is
+ // encoded by a single DCTDecode filter and decoding is a noop.
+ len = FPDFImageObj_GetImageDataDecoded(obj, nullptr, 0);
+ buf.clear();
+ buf.resize(len);
+ EXPECT_EQ(4370u, FPDFImageObj_GetImageDataDecoded(obj, buf.data(), len));
+ EXPECT_EQ("6aae1f3710335023a9e12191be66b64b",
+ GenerateMD5Base16(reinterpret_cast<uint8_t*>(buf.data()), len));
+
+ UnloadPage(page);
+}
diff --git a/fpdfsdk/fpdfeditimg.cpp b/fpdfsdk/fpdfeditimg.cpp
index bfd12b2..0d0c546 100644
--- a/fpdfsdk/fpdfeditimg.cpp
+++ b/fpdfsdk/fpdfeditimg.cpp
@@ -137,3 +137,45 @@
return pBitmap.Leak();
}
+
+DLLEXPORT unsigned long STDCALL
+FPDFImageObj_GetImageDataDecoded(FPDF_PAGEOBJECT image_object,
+ void* buffer,
+ unsigned long buflen) {
+ CPDF_PageObject* pObj = CPDFPageObjectFromFPDFPageObject(image_object);
+ if (!pObj || !pObj->IsImage())
+ return 0;
+
+ CFX_RetainPtr<CPDF_Image> pImg = pObj->AsImage()->GetImage();
+ if (!pImg)
+ return 0;
+
+ CPDF_Stream* pImgStream = pImg->GetStream();
+ if (!pImgStream)
+ return 0;
+
+ return DecodeStreamMaybeCopyAndReturnLength(pImgStream, buffer, buflen);
+}
+
+DLLEXPORT unsigned long STDCALL
+FPDFImageObj_GetImageDataRaw(FPDF_PAGEOBJECT image_object,
+ void* buffer,
+ unsigned long buflen) {
+ CPDF_PageObject* pObj = CPDFPageObjectFromFPDFPageObject(image_object);
+ if (!pObj || !pObj->IsImage())
+ return 0;
+
+ CFX_RetainPtr<CPDF_Image> pImg = pObj->AsImage()->GetImage();
+ if (!pImg)
+ return 0;
+
+ CPDF_Stream* pImgStream = pImg->GetStream();
+ if (!pImgStream)
+ return 0;
+
+ uint32_t len = pImgStream->GetRawSize();
+ if (buffer && buflen >= len)
+ memcpy(buffer, pImgStream->GetRawData(), len);
+
+ return len;
+}
diff --git a/fpdfsdk/fpdfview.cpp b/fpdfsdk/fpdfview.cpp
index 5aa8013..57e4806 100644
--- a/fpdfsdk/fpdfview.cpp
+++ b/fpdfsdk/fpdfview.cpp
@@ -357,10 +357,48 @@
unsigned long Utf16EncodeMaybeCopyAndReturnLength(const CFX_WideString& text,
void* buffer,
unsigned long buflen) {
- CFX_ByteString encodedText = text.UTF16LE_Encode();
- unsigned long len = encodedText.GetLength();
+ CFX_ByteString encoded_text = text.UTF16LE_Encode();
+ unsigned long len = encoded_text.GetLength();
if (buffer && len <= buflen)
- memcpy(buffer, encodedText.c_str(), len);
+ memcpy(buffer, encoded_text.c_str(), len);
+ return len;
+}
+
+unsigned long DecodeStreamMaybeCopyAndReturnLength(const CPDF_Stream* stream,
+ void* buffer,
+ unsigned long buflen) {
+ ASSERT(stream);
+ uint8_t* data = stream->GetRawData();
+ uint32_t len = stream->GetRawSize();
+ CPDF_Dictionary* dict = stream->GetDict();
+ CPDF_Object* decoder = dict ? dict->GetDirectObjectFor("Filter") : nullptr;
+ if (decoder && (decoder->IsArray() || decoder->IsName())) {
+ // Decode the stream if one or more stream filters are specified.
+ uint8_t* decoded_data = nullptr;
+ uint32_t decoded_len = 0;
+ CFX_ByteString dummy_last_decoder;
+ CPDF_Dictionary* dummy_last_param;
+ if (PDF_DataDecode(data, len, dict, dict->GetIntegerFor("DL"), false,
+ &decoded_data, &decoded_len, &dummy_last_decoder,
+ &dummy_last_param)) {
+ if (buffer && buflen >= decoded_len)
+ memcpy(buffer, decoded_data, decoded_len);
+
+ // Free the buffer for the decoded data if it was allocated by
+ // PDF_DataDecode(). Note that for images with a single image-specific
+ // filter, |decoded_data| is directly assigned to be |data|, so
+ // |decoded_data| does not need to be freed.
+ if (decoded_data != data)
+ FX_Free(decoded_data);
+
+ return decoded_len;
+ }
+ }
+ // Copy the raw data and return its length if there is no valid filter
+ // specified or if decoding failed.
+ if (buffer && buflen >= len)
+ memcpy(buffer, data, len);
+
return len;
}
diff --git a/fpdfsdk/fpdfview_c_api_test.c b/fpdfsdk/fpdfview_c_api_test.c
index e47f4d1..d40437c 100644
--- a/fpdfsdk/fpdfview_c_api_test.c
+++ b/fpdfsdk/fpdfview_c_api_test.c
@@ -133,6 +133,8 @@
CHK(FPDFImageObj_SetMatrix);
CHK(FPDFImageObj_SetBitmap);
CHK(FPDFImageObj_GetBitmap);
+ CHK(FPDFImageObj_GetImageDataDecoded);
+ CHK(FPDFImageObj_GetImageDataRaw);
CHK(FPDFPageObj_CreateNewPath);
CHK(FPDFPageObj_CreateNewRect);
CHK(FPDFPath_SetStrokeColor);
diff --git a/fpdfsdk/fsdk_define.h b/fpdfsdk/fsdk_define.h
index 610b854..91efc27 100644
--- a/fpdfsdk/fsdk_define.h
+++ b/fpdfsdk/fsdk_define.h
@@ -26,6 +26,7 @@
class CPDF_PageObject;
class CPDF_PageRenderContext;
class CPDF_PathObject;
+class CPDF_Stream;
class IFSDK_PAUSE_Adapter;
// Layering prevents fxcrt from knowing about FPDF_FILEACCESS, so this can't
@@ -77,6 +78,10 @@
void* buffer,
unsigned long buflen);
+unsigned long DecodeStreamMaybeCopyAndReturnLength(const CPDF_Stream* stream,
+ void* buffer,
+ unsigned long buflen);
+
void FSDK_SetSandBoxPolicy(FPDF_DWORD policy, FPDF_BOOL enable);
FPDF_BOOL FSDK_IsSandBoxPolicyEnabled(FPDF_DWORD policy);
void FPDF_RenderPage_Retail(CPDF_PageRenderContext* pContext,
