test7 works

pitfall/pitfall/alltest.rkt

@@ -7,5 +7,6 @@
            pitfall/test/test4
            pitfall/test/test5
            pitfall/test/test6
+           pitfall/test/test7
            pitfall/page-test
            (submod pitfall/zlib test)))

pitfall/pitfall/image.rkt

@@ -10,7 +10,7 @@
      )))
 
 (define/contract (PDFImage-open src label)
-  (any/c any/c . -> . (or/c (is-a?/c PNG)))
+  (any/c any/c . -> . (or/c (is-a?/c PNG) (is-a?/c JPEG)))
   (define data (cond
                  [(isBuffer? src) src]
                  ;;else if src instanceof ArrayBuffer
@@ -20,7 +20,7 @@
                  [else (file->bytes src)]))
   (cond
     [(equal? (subbytes data 0 2) (bytes #xff #xd8))
-     (error 'do-jpeg-unimplemented)]
+     (make-object JPEG data label)]
     [(equal? (subbytes data 0 4) (apply bytes (cons #x89 (map char->integer '(#\P #\N #\G)))))
      (make-object PNG data label)]
     [else (raise-argument-error 'PDFImage-open "valid image format" src)]))

pitfall/pitfall/jpeg.rkt

@@ -1 +1,74 @@
 #lang pitfall/racket
+(provide JPEG)
+
+(define MARKERS '(#xffc0 #xffc1 #xffc2 #xffc3 #xffc5 #xffc6 #xffc7
+                         #xffc8 #xffc9 #xffca #xffcb #xffcc #xffcd #xffce #xffcf))
+
+(define-subclass object% (JPEG data [label #f])
+  (super-new)
+  (define last-ip (current-input-port))
+  (current-input-port (if (input-port? data)
+                          data
+                          (open-input-bytes data)))
+  (unless (equal? (read-16bit-integer) #xffd8)
+    (error 'JPEG "Start of Input marker byte not found"))
+
+  (define marker (let loop ([skip 0])
+                   (read-bytes skip)
+                   (define m (read-16bit-integer))
+                   (if (memv m MARKERS)
+                       m
+                       (loop (read-16bit-integer (peek-bytes 2 0))))))
+                         
+  (read-16bit-integer)
+  (field [bits (read-byte)]
+         [height (read-16bit-integer)]
+         [width (read-16bit-integer)]
+         [channels (read-byte)]
+         [colorSpace (case channels
+                       [(1) "DeviceGray"]
+                       [(3) "DeviceRGB"]
+                       [(4) "DeviceCMYK"])]
+         [obj #f])
+
+  (current-input-port last-ip)
+
+  (as-methods
+   embed))
+
+(define (read-16bit-integer [bytes-or-port #f])
+  (define signed #f) (define big-endian #t)
+  (integer-bytes->integer (read-bytes 2 (cond
+                                          [(bytes? bytes-or-port)
+                                           (open-input-bytes bytes-or-port)]
+                                          [(port? bytes-or-port) bytes-or-port]
+                                          [else
+                                           (current-input-port)])) signed big-endian))
+
+(define/contract (embed this doc-in)
+  (object? . ->m . void?)
+
+  (unless (· this obj)
+    (set-field! obj this
+                (send doc-in ref
+                      (mhash
+                       'Type "XObject"
+                       'Subtype "Image"
+                       'BitsPerComponent (· this bits)
+                       'Width (· this width)
+                       'Height (· this height)
+                       'ColorSpace (· this colorSpace)
+                       'Filter "DCTDecode")))
+    
+    ;; add extra decode params for CMYK images. By swapping the
+    ;; min and max values from the default, we invert the colors. See
+    ;; section 4.8.4 of the spec. 
+    (when (equal? (· this colorSpace) "DeviceCMYK")
+      (hash-set! (· this obj payload) 'Decode '(1.0 0.0 1.0 0.0 1.0 0.0 1.0 0.0)))
+
+    (send (· this obj) end (· this data))))
+
+(module+ test
+  (require rackunit)
+  (check-equal? (number->string (read-16bit-integer (bytes #x12 #x34 #x56)) 16) "1234")
+  (make-object JPEG (open-input-file "test/assets/test.jpeg")))

pitfall/pitfall/png-reader.rkt

@@ -47,7 +47,8 @@ Grab key chunks from PNG. Doesn't require heavy lifting from libpng.
          (loop)]))))
 
 (define (read-32bit-integer)
-  (integer-bytes->integer (read-bytes 4) #t #t))
+  (define signed #f) (define big-endian #t)
+  (integer-bytes->integer (read-bytes 4) signed big-endian))
 
 (module+ test
   (require rackunit)

pitfall/pitfall/png.rkt

@@ -9,19 +9,17 @@
          [width (· image width)]
          [height (· image height)]
          [imgData (· image imgData)]
-         [obj #f]
+         [obj #f])
-         [document #f])
 
   (as-methods
    embed))
 
 (define/contract (embed this doc-in)
   (object? . ->m . void?)
-  (set-field! document this doc-in)
   
   (unless (· this obj)
     (set-field! obj this
-                (send (· this document) ref
+                (send doc-in ref
                       (mhash 'Type "XObject"
                              'Subtype "Image"
                              'BitsPerComponent (· this image bits)
@@ -30,7 +28,7 @@
                              'Filter "FlateDecode")))
 
     (unless (· this image hasAlphaChannel)
-      (define params (send (· this document) ref (mhash 'Predictor 15
+      (define params (send doc-in ref (mhash 'Predictor 15
                                                         'Colors (· this image colors)
                                                         'BitsPerComponent (· this image bits)
                                                         'Columns (· this width))))
@@ -40,7 +38,7 @@
     (cond
       [(hash-ref (· this image) 'palette #f)
        ;; embed the color palette in the PDF as an object stream
-       (define palette-ref (· this document ref))
+       (define palette-ref (· doc-in ref))
        (send palette-ref end (· this image palette))
 
        ;; build the color space array for the image

pitfall/pitfall/test/test5 copy.coffee

@@ -0,0 +1,20 @@
+PDFDocument = require 'pdfkit'
+fs = require 'fs'
+
+make = (doc) -> 
+    # Set the font, draw some text, and embed an image
+    doc.font('Times-Italic')
+       .fontSize(25)
+       .text('Here comes a JPEG!', 100, 100, lineBreak: no)
+       .image('assets/test.jpeg', 100, 160, width: 412)
+
+    doc.end()
+
+doc = new PDFDocument({compress: no})
+doc.pipe(fs.createWriteStream('test5.pdf'))
+make doc
+
+doc = new PDFDocument({compress: yes})
+doc.pipe(fs.createWriteStream('test5c.pdf'))
+make doc
+

pitfall/pitfall/test/test5.coffee

@@ -6,7 +6,7 @@ make = (doc) ->
     doc.font('Times-Italic')
        .fontSize(25)
        .text('Some fantastic text!', 100, 100, lineBreak: no)
-       .image('death.png', 100, 160, width: 412)
+       .image('assets/death.png', 100, 160, width: 412)
 
     doc.end()
 

pitfall/pitfall/test/test5.rkt

@@ -1,6 +1,6 @@
 #lang pitfall/pdftest
 
-(define-runtime-path death "death.png")
+(define-runtime-path death "assets/death.png")
 
 (define (proc doc)
   (send* doc

pitfall/pitfall/test/test7.rkt

@@ -0,0 +1,16 @@
+#lang pitfall/pdftest
+
+(define-runtime-path test-jpeg "assets/test.jpeg")
+
+(define (proc doc)
+  (send* doc
+  [font "Times-Italic"]
+  [fontSize 25]
+  [text "Here comes a JPEG!" 100 100 (hash 'lineBreak #f)]
+  [image test-jpeg 100 160 (hash 'width 412)]))
+
+(define-runtime-path this "test7rkt.pdf")
+(make-doc this #f proc)
+
+(define-runtime-path that "test7crkt.pdf")
+(make-doc that #t proc)