Added support for Illustrator previews (%AI7_Thumbnail) in EPS files, decoded to *.pnm

src/epsimage.cpp

@@ -417,6 +417,8 @@ namespace {
         size_t posExiv2Version = posEndEps;
         size_t posExiv2Website = posEndEps;
         size_t posEndComments = posEndEps;
+        size_t posAi7Thumbnail = posEndEps;
+        size_t posAi7ThumbnailEndData = posEndEps;
         size_t posBeginPhotoshop = posEndEps;
         size_t posEndPhotoshop = posEndEps;
         size_t posPage = posEndEps;
@@ -543,6 +545,10 @@ namespace {
                 posExiv2Website = startPos;
             } else if (posEndComments == posEndEps && startsWith(line, "%%Creator: Adobe Illustrator") && firstLine == "%!PS-Adobe-3.0 EPSF-3.0") {
                 illustrator8 = true;
+            } else if (posEndComments == posEndEps && startsWith(line, "%AI7_Thumbnail:")) {
+                posAi7Thumbnail = startPos;
+            } else if (posEndComments == posEndEps && posAi7Thumbnail != posEndEps && posAi7ThumbnailEndData == posEndEps && line == "%%EndData") {
+                posAi7ThumbnailEndData = startPos;
             } else if (posEndComments == posEndEps && line == "%%EndComments") {
                 posEndComments = startPos;
             } else if (line == "%%EndPreview") {
@@ -711,6 +717,45 @@ namespace {
 
             // native previews
             nativePreviews.clear();
+            if (posAi7ThumbnailEndData != posEndEps) {
+                NativePreview nativePreview;
+                std::string dummy;
+                std::string lineAi7Thumbnail;
+                const size_t posBeginData = readLine(lineAi7Thumbnail, data, posAi7Thumbnail, posEndEps);
+                std::istringstream lineStreamAi7Thumbnail(lineAi7Thumbnail);
+                lineStreamAi7Thumbnail >> dummy;
+                lineStreamAi7Thumbnail >> nativePreview.width_;
+                lineStreamAi7Thumbnail >> nativePreview.height_;
+                std::string depth;
+                lineStreamAi7Thumbnail >> depth;
+                std::string lineBeginData;
+                const size_t posAfterBeginData = readLine(lineBeginData, data, posBeginData, posEndEps);
+                std::istringstream lineStreamBeginData(lineBeginData);
+                std::string beginData;
+                lineStreamBeginData >> beginData;
+                lineStreamBeginData >> dummy;
+                std::string type;
+                lineStreamBeginData >> type;
+                nativePreview.position_ = static_cast<long>(posAfterBeginData);
+                nativePreview.size_ = posAi7ThumbnailEndData - posAfterBeginData;
+                nativePreview.filter_ = "hex-ai7thumbnail-pnm";
+                nativePreview.mimeType_ = "image/x-portable-anymap";
+                if (depth != "8") {
+                    #ifndef SUPPRESS_WARNINGS
+                    EXV_WARNING << "Unable to handle Illustrator thumbnail depth: " << depth << "\n";
+                    #endif
+                } else if (beginData != "%%BeginData:") {
+                    #ifndef SUPPRESS_WARNINGS
+                    EXV_WARNING << "Unable to handle Illustrator thumbnail data section: " << lineBeginData << "\n";
+                    #endif
+                } else if (type != "Hex") {
+                    #ifndef SUPPRESS_WARNINGS
+                    EXV_WARNING << "Unable to handle Illustrator thumbnail data type: " << type << "\n";
+                    #endif
+                } else {
+                    nativePreviews.push_back(nativePreview);
+                }
+            }
             if (posEndPhotoshop != posEndEps) {
                 NativePreview nativePreview;
                 nativePreview.position_ = static_cast<long>(posBeginPhotoshop);

src/epsimage.hpp

@@ -25,6 +25,7 @@
            <br>[1] <a href="http://partners.adobe.com/public/developer/en/ps/5001.DSC_Spec.pdf">Adobe PostScript Language Document Structuring Conventions Specification, Version 3.0</a>, September 1992
            <br>[2] <a href="http://partners.adobe.com/public/developer/en/ps/5002.EPSF_Spec.pdf">Adobe Encapsulated PostScript File Format Specification, Version 3.0</a>, May 1992
            <br>[3] <a href="http://www.adobe.com/content/dam/Adobe/en/devnet/xmp/pdfs/XMPSpecificationPart3.pdf">Adobe XMP Specification Part 3: Storage in Files</a>, July 2010
+           <br>[4] <a href="http://groups.google.com/group/adobe.illustrator.windows/msg/0a9d7b1244b59062">Re: Thumbnail data format in ai file</a>, Dec 2003
   @version $Rev: $
   @author  Michael Ulbrich (mul)
            <a href="mailto:mul@rentapacs.de">mul@rentapacs.de</a>

src/preview.cpp

@@ -78,6 +78,16 @@ namespace {
      */
     DataBuf decodeBase64(const std::string &src);
 
+    /*!
+      @brief Decode an Illustrator thumbnail that follows after %AI7_Thumbnail.
+     */
+    DataBuf decodeAi7Thumbnail(const DataBuf &src);
+
+    /*!
+      @brief Create a PNM image from raw RGB data.
+     */
+    DataBuf makePnm(uint32_t width, uint32_t height, const DataBuf &rgb);
+
     /*!
       Base class for image loaders. Provides virtual methods for reading properties
       and DataBuf.
@@ -434,6 +444,8 @@ namespace {
             prop.extension_ = ".tif";
         } else if (nativePreview_.mimeType_ == "image/x-wmf") {
             prop.extension_ = ".wmf";
+        } else if (nativePreview_.mimeType_ == "image/x-portable-anymap") {
+            prop.extension_ = ".pnm";
         } else {
 #ifndef SUPPRESS_WARNINGS
             EXV_WARNING << "Unknown native preview format: " << nativePreview_.mimeType_ << "\n";
@@ -464,6 +476,10 @@ namespace {
         }
         if (nativePreview_.filter_ == "") {
             return DataBuf(data + nativePreview_.position_, static_cast<long>(nativePreview_.size_));
+        } else if (nativePreview_.filter_ == "hex-ai7thumbnail-pnm") {
+            const DataBuf ai7thumbnail = decodeHex(data + nativePreview_.position_, static_cast<long>(nativePreview_.size_));
+            const DataBuf rgb = decodeAi7Thumbnail(ai7thumbnail);
+            return makePnm(width_, height_, rgb);
         } else if (nativePreview_.filter_ == "hex-irb") {
             const DataBuf psData = decodeHex(data + nativePreview_.position_, static_cast<long>(nativePreview_.size_));
             const byte *record;
@@ -957,6 +973,68 @@ namespace {
         return dest;
     }
 
+    DataBuf decodeAi7Thumbnail(const DataBuf &src)
+    {
+        const byte *colorTable = src.pData_;
+        const long colorTableSize = 256 * 3;
+        if (src.size_ < colorTableSize) {
+#ifndef SUPPRESS_WARNINGS
+            EXV_WARNING << "Invalid size of AI7 thumbnail: " << src.size_ << "\n";
+#endif
+            return DataBuf();
+        }
+        const byte *imageData = src.pData_ + colorTableSize;
+        const long imageDataSize = src.size_ - colorTableSize;
+        const bool rle = (imageDataSize >= 3 && imageData[0] == 'R' && imageData[1] == 'L' && imageData[2] == 'E');
+        std::string dest;
+        for (long i = rle ? 3 : 0; i < imageDataSize;) {
+            byte num = 1;
+            byte value = imageData[i++];
+            if (rle && value == 0xFD) {
+                if (i >= imageDataSize) {
+#ifndef SUPPRESS_WARNINGS
+                    EXV_WARNING << "Unexpected end of image data at AI7 thumbnail.\n";
+#endif
+                    return DataBuf();
+                }
+                value = imageData[i++];
+                if (value != 0xFD) {
+                    if (i >= imageDataSize) {
+#ifndef SUPPRESS_WARNINGS
+                        EXV_WARNING << "Unexpected end of image data at AI7 thumbnail.\n";
+#endif
+                        return DataBuf();
+                    }
+                    num = value;
+                    value = imageData[i++];
+                }
+            }
+            for (; num != 0; num--) {
+                dest.append(reinterpret_cast<const char*>(colorTable + (3*value)), 3);
+            }
+        }
+        return DataBuf(reinterpret_cast<const byte*>(dest.data()), static_cast<long>(dest.size()));
+    }
+
+    DataBuf makePnm(uint32_t width, uint32_t height, const DataBuf &rgb)
+    {
+        const long expectedSize = static_cast<long>(width * height * 3);
+        if (rgb.size_ != expectedSize) {
+#ifndef SUPPRESS_WARNINGS
+            EXV_WARNING << "Invalid size of preview data. Expected " << expectedSize << " bytes, got " << rgb.size_ << " bytes.\n";
+#endif
+            return DataBuf();
+        }
+
+        const std::string header = "P6\n" + toString(width) + " " + toString(height) + "\n255\n";
+        const byte *headerBytes = reinterpret_cast<const byte*>(header.data());
+
+        DataBuf dest(header.size() + rgb.size_);
+        std::copy(headerBytes, headerBytes + header.size(), dest.pData_);
+        std::copy(rgb.pData_, rgb.pData_ + rgb.size_, dest.pData_ + header.size());
+        return dest;
+    }
+
 }                                       // namespace
 
 // *****************************************************************************

test/data/preview/preview-test.out

@@ -14,7 +14,8 @@ Exit code: 1
 -----> eps-flat_oodraw_ai-10-lev2.eps <-----
 
 Command: exiv2 -pp eps-flat_oodraw_ai-10-lev2.eps
-Preview 1: image/jpeg, 256x208 pixels, 3166 bytes
+Preview 1: image/x-portable-anymap, 128x104 pixels, 39951 bytes
+Preview 2: image/jpeg, 256x208 pixels, 3166 bytes
 Exit code: 0
 
 Command: exiv2 -f -ep eps-flat_oodraw_ai-10-lev2.eps
@@ -23,7 +24,8 @@ Exit code: 0
 -----> eps-flat_oodraw_ai-8-lev2.eps <-----
 
 Command: exiv2 -pp eps-flat_oodraw_ai-8-lev2.eps
-Preview 1: image/jpeg, 256x208 pixels, 3166 bytes
+Preview 1: image/x-portable-anymap, 128x104 pixels, 39951 bytes
+Preview 2: image/jpeg, 256x208 pixels, 3166 bytes
 Exit code: 0
 
 Command: exiv2 -f -ep eps-flat_oodraw_ai-8-lev2.eps
@@ -32,6 +34,7 @@ Exit code: 0
 -----> eps-flat_oodraw_ai-8-lev3.eps <-----
 
 Command: exiv2 -pp eps-flat_oodraw_ai-8-lev3.eps
+Preview 1: image/x-portable-anymap, 128x104 pixels, 39951 bytes
 Exit code: 0
 
 Command: exiv2 -f -ep eps-flat_oodraw_ai-8-lev3.eps
@@ -40,7 +43,8 @@ Exit code: 0
 -----> eps-flat_oodraw_ai-9-lev2.eps <-----
 
 Command: exiv2 -pp eps-flat_oodraw_ai-9-lev2.eps
-Preview 1: image/jpeg, 256x208 pixels, 3166 bytes
+Preview 1: image/x-portable-anymap, 128x104 pixels, 39951 bytes
+Preview 2: image/jpeg, 256x208 pixels, 3166 bytes
 Exit code: 0
 
 Command: exiv2 -f -ep eps-flat_oodraw_ai-9-lev2.eps
@@ -49,7 +53,8 @@ Exit code: 0
 -----> eps-flat_oodraw_ai-cs-lev2.eps <-----
 
 Command: exiv2 -pp eps-flat_oodraw_ai-cs-lev2.eps
-Preview 1: image/jpeg, 256x208 pixels, 3166 bytes
+Preview 1: image/x-portable-anymap, 128x104 pixels, 39951 bytes
+Preview 2: image/jpeg, 256x208 pixels, 3166 bytes
 Exit code: 0
 
 Command: exiv2 -f -ep eps-flat_oodraw_ai-cs-lev2.eps
@@ -58,7 +63,8 @@ Exit code: 0
 -----> eps-flat_oodraw_ai-cs2-lev2.eps <-----
 
 Command: exiv2 -pp eps-flat_oodraw_ai-cs2-lev2.eps
-Preview 1: image/jpeg, 256x208 pixels, 3166 bytes
+Preview 1: image/x-portable-anymap, 128x104 pixels, 39951 bytes
+Preview 2: image/jpeg, 256x208 pixels, 3166 bytes
 Exit code: 0
 
 Command: exiv2 -f -ep eps-flat_oodraw_ai-cs2-lev2.eps
@@ -67,7 +73,8 @@ Exit code: 0
 -----> eps-flat_oodraw_ai-cs3-lev2.eps <-----
 
 Command: exiv2 -pp eps-flat_oodraw_ai-cs3-lev2.eps
-Preview 1: image/jpeg, 256x208 pixels, 3166 bytes
+Preview 1: image/x-portable-anymap, 128x104 pixels, 39951 bytes
+Preview 2: image/jpeg, 256x208 pixels, 3166 bytes
 Exit code: 0
 
 Command: exiv2 -f -ep eps-flat_oodraw_ai-cs3-lev2.eps
@@ -76,7 +83,8 @@ Exit code: 0
 -----> eps-flat_oodraw_ai-cs4-lev2.eps <-----
 
 Command: exiv2 -pp eps-flat_oodraw_ai-cs4-lev2.eps
-Preview 1: image/jpeg, 256x208 pixels, 3166 bytes
+Preview 1: image/x-portable-anymap, 128x104 pixels, 39951 bytes
+Preview 2: image/jpeg, 256x208 pixels, 3166 bytes
 Exit code: 0
 
 Command: exiv2 -f -ep eps-flat_oodraw_ai-cs4-lev2.eps
@@ -85,7 +93,8 @@ Exit code: 0
 -----> eps-flat_oodraw_ai-cs5-lev2.eps <-----
 
 Command: exiv2 -pp eps-flat_oodraw_ai-cs5-lev2.eps
-Preview 1: image/jpeg, 256x208 pixels, 3166 bytes
+Preview 1: image/x-portable-anymap, 128x104 pixels, 39951 bytes
+Preview 2: image/jpeg, 256x208 pixels, 3166 bytes
 Exit code: 0
 
 Command: exiv2 -f -ep eps-flat_oodraw_ai-cs5-lev2.eps
@@ -103,8 +112,9 @@ Exit code: 0
 -----> eps-flat_oodraw_ai-cs5-lev3-pre.eps <-----
 
 Command: exiv2 -pp eps-flat_oodraw_ai-cs5-lev3-pre.eps
-Preview 1: image/tiff, 213x170 pixels, 37902 bytes
-Preview 2: image/jpeg, 256x208 pixels, 3166 bytes
+Preview 1: image/x-portable-anymap, 128x104 pixels, 39951 bytes
+Preview 2: image/tiff, 213x170 pixels, 37902 bytes
+Preview 3: image/jpeg, 256x208 pixels, 3166 bytes
 Exit code: 0
 
 Command: exiv2 -f -ep eps-flat_oodraw_ai-cs5-lev3-pre.eps
@@ -113,7 +123,8 @@ Exit code: 0
 -----> eps-flat_oodraw_ai-cs5-lev3.eps <-----
 
 Command: exiv2 -pp eps-flat_oodraw_ai-cs5-lev3.eps
-Preview 1: image/jpeg, 256x208 pixels, 3166 bytes
+Preview 1: image/x-portable-anymap, 128x104 pixels, 39951 bytes
+Preview 2: image/jpeg, 256x208 pixels, 3166 bytes
 Exit code: 0
 
 Command: exiv2 -f -ep eps-flat_oodraw_ai-cs5-lev3.eps
@@ -122,6 +133,7 @@ Exit code: 0
 -----> eps-flat_oodraw_ai-cs5-lev3_exiftool-8.56.eps <-----
 
 Command: exiv2 -pp eps-flat_oodraw_ai-cs5-lev3_exiftool-8.56.eps
+Preview 1: image/x-portable-anymap, 128x104 pixels, 39951 bytes
 Exit code: 0
 
 Command: exiv2 -f -ep eps-flat_oodraw_ai-cs5-lev3_exiftool-8.56.eps
@@ -130,7 +142,8 @@ Exit code: 0
 -----> eps-flat_oodraw_ai-cs5-lev3_ns-xapGImg.eps <-----
 
 Command: exiv2 -pp eps-flat_oodraw_ai-cs5-lev3_ns-xapGImg.eps
-Preview 1: image/jpeg, 256x208 pixels, 3166 bytes
+Preview 1: image/x-portable-anymap, 128x104 pixels, 39951 bytes
+Preview 2: image/jpeg, 256x208 pixels, 3166 bytes
 Exit code: 0
 
 Command: exiv2 -f -ep eps-flat_oodraw_ai-cs5-lev3_ns-xapGImg.eps