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jpeg.lisp
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jpeg.lisp
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;;; ANSI Common Lisp (mostly) baseline JPEG encoder/decoder implementation
;;; Copyright [c] 1999,2015-2017 Eugene Zaikonnikov <eugene@funcall.org>
;;;
;;; This software is distributed under the terms of BSD-like license
;;; [see LICENSE for details]
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; This software was sponsored by Kelly E. Murray
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; Two main functions available:
;;;
;;; (encode-image filename image ncomp h w &key sampling q-tabs q-factor), where:
;;; filename - output file name
;;; ncomp - number of components (1-4)
;;; h, w - source image height and width respectively
;;; image - array of B, G, R pixels in case of three component image,
;;; array of grayscale pixels in case of single component,
;;; array of 2 or 4 pixels in the case of two or four component image respectively
;;; :q-tabs - specifies quantization tables vector, should be 1 for 1,
;;; 2 for 2, 2 for 3 and 4 entries for 4 components
;;; :sampling - sampling frequency for ncomp components by X and Y axis,
;;; e.g. '((2 2) (1 1) (1 1)) for three components, can be omitted
;;; for grayscale and RGB images
;;; :q-factor - quality specifier (1-64), default is 64
;;; Returns nothing of practical use
;;;
;;; (decode-image filename &key buffer (colorspace-conversion t))
;;; filename - jpeg file name
;;; Returns (multiple-valued) IMAGE array in the same format as encoder source image,
;;; image HEIGHT and image WIDTH
;;; A pre-allocated BUFFER can be specified (see JPEG:ALLOCATE-BUFFER).
;;; If :colorspace-conversion is NIL, no conversion from YUV space is performed.
;;;
;;; For those impatient additional function defined:
;;; (jpeg-to-bmp &key infile outfile)
;;; Converts JPEG image specified by infile into Microsoft Windows 24-bit BMP format (outfile),
;;; returns NIL
;;;
;;; Additionaly, you may use more user-friendly version of encode-image: encode-wrapper.
;;; (encoding-wrapper filename image ncomp h w &key quality)
;;; All parameters have the same meaning as in encode-image, except quality.
;;; It is an integer value ranging 1 to 5 which specifies
;;; subjective quality of a resulting image.
;;; Technical details: encoder produces interleaved jpeg file, without restarts.
;;; In a case of 3 components image will be written in JFIF format.
;;; Decoder can deal with *almost* all baseline jpeg files, regardless JFIF or not.
;;; It supports restarts, interleaved/noninterleaved files, multiscan images, 1 to 4 color
;;; channels, up to 4 quantization tables and two sets of huffman tables with random order
;;; of their definition inside the image. Decoder *does not* support DNL marker, due to
;;; it's rarity and amount of work needed to implement it, so decoder isn't baseline in a
;;; strict sense.
;;; Both encoder and decoder utilize Loeffer, Ligtenberg and Moschytz integer discrete
;;; cosine transform algorithms with 12 multiplications in each loop.
;;; Based on CCITT Rec. T.81
;;; "Information technology - digital compression and coding of continious-tone still images
;;; - requirements and guidelines".
;;; Credits:
;;; to the Independent JPEG Group -
;;; colorspace conversion and DCT algorithms were adopted from their sources;
;;; to Jeff Dalton for his wise paper "Common Lisp Pitfalls".
(in-package #:jpeg)
(declaim (inline csize quantize get-average zigzag read-jpeg-byte
llm-dct descale crunch colorspace-convert subsample inverse-llm-dct
dequantize upsample extend recieve decode-ac decode-dc decode-block
izigzag write-bits limit))
(deftype uint8 () '(unsigned-byte 8))
(deftype uint8-array () '(simple-array uint8 (*)))
(deftype uint8-2d-array () '(simple-array uint8-array (*)))
(deftype suint8 () '(signed-byte 8))
(deftype sint8-array () '(simple-array sint8 (*)))
(deftype sint8-2d-array () '(simple-array sint8-array (*)))
(deftype sint16 () '(signed-byte 16))
(deftype sint16-array () '(simple-array sint16 (*)))
(deftype sint16-2d-array () '(simple-array sint16-array (*)))
(deftype uint16 () '(unsigned-byte 16))
(deftype uint16-array () '(simple-array uint16 (*)))
(deftype uint16-2d-array () '(simple-array uint16-array (*)))
(deftype fixnum-array () '(simple-array fixnum (*)))
(deftype fixnum-2d-array () '(simple-array fixnum-array (*)))
(eval-when (:compile-toplevel :load-toplevel :execute)
(defparameter *optimize* '(optimize (safety 0) (space 0) (debug 0) (speed 3))))
(eval-when (:compile-toplevel :load-toplevel :execute)
;;; For ease of reference
(defmacro u8ref (data x y)
`(the uint8 (aref (the uint8-array (aref (the uint8-2d-array ,data) ,y)) ,x)))
(defmacro s16ref (data x y)
`(the sint16 (aref (the sint16-array (aref (the sint16-2d-array ,data) ,y)) ,x)))
(defmacro u16ref (data x y)
`(the uint16 (aref (the uint16-array (aref (the uint16-2d-array ,data) ,y)) ,x)))
(defmacro fixref (data x y)
`(the fixnum (aref (the fixnum-array (aref (the fixnum-2d-array ,data) ,y)) ,x)))
;;; Integer arithmetic wrappers
(defmacro plus (a b)
`(the fixnum (+ (the fixnum ,a) (the fixnum ,b))))
(defmacro minus (a b)
#+(or clisp abcl)
`(- ,a ,b)
#-(or clisp abcl)
`(the fixnum (- (the fixnum ,a) (the fixnum ,b))))
(defmacro mul (a b)
`(the fixnum (* (the fixnum ,a) (the fixnum ,b))))
(defmacro plus3 (x y z)
`(plus (plus ,x ,y) ,z))
(defmacro mul3 (x y z)
`(mul (mul ,x ,y) ,z)))
;;; Somewhat silly, but who knows...
(when (/= (integer-length most-positive-fixnum)
(integer-length most-negative-fixnum))
(error "Can't compile with asymmetric fixnums!"))
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; Here we define some constants (markers, quantization and huffman tables etc.)
(defmacro define-constant (name value &optional doc)
`(defconstant ,name (if (boundp ',name) (symbol-value ',name) ,value)
,@(when doc (list doc))))
(eval-when (:compile-toplevel :load-toplevel)
(defun uint8-array (&rest contents)
(the uint8-array (make-array (length contents) :element-type 'uint8
:initial-contents contents)))
(defun 2d-uint8-array (&rest contents)
(let ((nrow (length contents)))
(the uint8-2d-array
(make-array nrow
:element-type 'uint8-array
:initial-contents
(loop for row in contents
collecting (make-array (length row) :element-type 'uint8
:initial-contents row))))))
(defun 2d-sint16-array (&rest contents)
(let ((nrow (length contents)))
(the sint16-2d-array
(make-array nrow
:element-type 'sint16-array
:initial-contents
(loop for row in contents
collecting (make-array (length row) :element-type 'sint16
:initial-contents row))))))
;;; Source huffman tables for the encoder
(define-constant +luminance-dc-bits+
(uint8-array #x00 #x01 #x05 #x01 #x01 #x01 #x01 #x01
#x01 #x00 #x00 #x00 #x00 #x00 #x00 #x00))
(define-constant +luminance-dc-values+
(uint8-array #x00 #x01 #x02 #x03 #x04 #x05 #x06 #x07 #x08 #x09 #x0a #x0b))
(define-constant +chrominance-dc-bits+
(uint8-array #x00 #x03 #x01 #x01 #x01 #x01 #x01 #x01
#x01 #x01 #x01 #x00 #x00 #x00 #x00 #x00))
(define-constant +chrominance-dc-values+
(uint8-array #x00 #x01 #x02 #x03 #x04 #x05 #x06 #x07 #x08 #x09 #x0a #x0b))
(define-constant +luminance-ac-bits+
(uint8-array #x00 #x02 #x01 #x03 #x03 #x02 #x04 #x03
#x05 #x05 #x04 #x04 #x00 #x00 #x01 #x7d))
(define-constant +luminance-ac-values+
(uint8-array
#x01 #x02 #x03 #x00 #x04 #x11 #x05 #x12
#x21 #x31 #x41 #x06 #x13 #x51 #x61 #x07
#x22 #x71 #x14 #x32 #x81 #x91 #xa1 #x08
#x23 #x42 #xb1 #xc1 #x15 #x52 #xd1 #xf0
#x24 #x33 #x62 #x72 #x82 #x09 #x0a #x16
#x17 #x18 #x19 #x1a #x25 #x26 #x27 #x28
#x29 #x2a #x34 #x35 #x36 #x37 #x38 #x39
#x3a #x43 #x44 #x45 #x46 #x47 #x48 #x49
#x4a #x53 #x54 #x55 #x56 #x57 #x58 #x59
#x5a #x63 #x64 #x65 #x66 #x67 #x68 #x69
#x6a #x73 #x74 #x75 #x76 #x77 #x78 #x79
#x7a #x83 #x84 #x85 #x86 #x87 #x88 #x89
#x8a #x92 #x93 #x94 #x95 #x96 #x97 #x98
#x99 #x9a #xa2 #xa3 #xa4 #xa5 #xa6 #xa7
#xa8 #xa9 #xaa #xb2 #xb3 #xb4 #xb5 #xb6
#xb7 #xb8 #xb9 #xba #xc2 #xc3 #xc4 #xc5
#xc6 #xc7 #xc8 #xc9 #xca #xd2 #xd3 #xd4
#xd5 #xd6 #xd7 #xd8 #xd9 #xda #xe1 #xe2
#xe3 #xe4 #xe5 #xe6 #xe7 #xe8 #xe9 #xea
#xf1 #xf2 #xf3 #xf4 #xf5 #xf6 #xf7 #xf8
#xf9 #xfa))
(define-constant +chrominance-ac-bits+
(uint8-array #x00 #x02 #x01 #x02 #x04 #x04 #x03 #x04
#x07 #x05 #x04 #x04 #x00 #x01 #x02 #x77))
(define-constant +chrominance-ac-values+
(uint8-array
#x00 #x01 #x02 #x03 #x11 #x04 #x05 #x21
#x31 #x06 #x12 #x41 #x51 #x07 #x61 #x71
#x13 #x22 #x32 #x81 #x08 #x14 #x42 #x91
#xa1 #xb1 #xc1 #x09 #x23 #x33 #x52 #xf0
#x15 #x62 #x72 #xd1 #x0a #x16 #x24 #x34
#xe1 #x25 #xf1 #x17 #x18 #x19 #x1a #x26
#x27 #x28 #x29 #x2a #x35 #x36 #x37 #x38
#x39 #x3a #x43 #x44 #x45 #x46 #x47 #x48
#x49 #x4a #x53 #x54 #x55 #x56 #x57 #x58
#x59 #x5a #x63 #x64 #x65 #x66 #x67 #x68
#x69 #x6a #x73 #x74 #x75 #x76 #x77 #x78
#x79 #x7a #x82 #x83 #x84 #x85 #x86 #x87
#x88 #x89 #x8a #x92 #x93 #x94 #x95 #x96
#x97 #x98 #x99 #x9a #xa2 #xa3 #xa4 #xa5
#xa6 #xa7 #xa8 #xa9 #xaa #xb2 #xb3 #xb4
#xb5 #xb6 #xb7 #xb8 #xb9 #xba #xc2 #xc3
#xc4 #xc5 #xc6 #xc7 #xc8 #xc9 #xca #xd2
#xd3 #xd4 #xd5 #xd6 #xd7 #xd8 #xd9 #xda
#xe2 #xe3 #xe4 #xe5 #xe6 #xe7 #xe8 #xe9
#xea #xf2 #xf3 #xf4 #xf5 #xf6 #xf7 #xf8
#xf9 #xfa))
;;;Zigzag encoding matrix
(define-constant +zigzag-index+
(2d-uint8-array '(0 1 5 6 14 15 27 28)
'(2 4 7 13 16 26 29 42)
'(3 8 12 17 25 30 41 43)
'(9 11 18 24 31 40 44 53)
'(10 19 23 32 39 45 52 54)
'(20 22 33 38 46 51 55 60)
'(21 34 37 47 50 56 59 61)
'(35 36 48 49 57 58 62 63)))
;;;JPEG file markers
(defconstant +M_COM+ #xfe)
(defconstant +M_SOF0+ #xc0)
(defconstant +M_SOF2+ #xc2)
(defconstant +M_DHT+ #xc4)
(defconstant +M_RST0+ #xd0)
(defconstant +M_RST7+ #xd7)
(defconstant +M_SOI+ #xd8)
(defconstant +M_EOI+ #xd9)
(defconstant +M_SOS+ #xda)
(defconstant +M_DQT+ #xdb)
(defconstant +M_DNL+ #xdc)
(defconstant +M_DRI+ #xdd)
(defconstant +M_DAC+ #xcc)
(defconstant +M_APP0+ #xe0)
(defconstant +M_APP14+ #xee)
;;; Default quantization tables
(define-constant +q-luminance+
(2d-uint8-array '(16 11 10 16 24 40 51 61)
'(12 12 14 19 26 58 60 55)
'(14 13 16 24 40 57 69 56)
'(14 17 22 29 51 87 80 62)
'(18 22 37 56 68 109 103 77)
'(24 35 55 64 81 104 113 92)
'(49 64 78 87 103 121 120 101)
'(72 92 95 98 112 100 103 99)))
(define-constant +q-chrominance+
(2d-uint8-array '(17 18 24 47 99 99 99 99)
'(18 21 26 66 99 99 99 99)
'(24 26 56 99 99 99 99 99)
'(47 66 99 99 99 99 99 99)
'(99 99 99 99 99 99 99 99)
'(99 99 99 99 99 99 99 99)
'(99 99 99 99 99 99 99 99)
'(99 99 99 99 99 99 99 99)))
(define-constant +q-luminance-hi+
(2d-uint8-array '(10 7 6 10 15 25 32 38)
'(8 8 9 12 16 36 38 34)
'(9 8 10 15 25 36 43 35)
'(9 11 14 18 32 54 50 39)
'(11 14 23 35 42 68 64 48)
'(15 22 34 40 51 65 71 58)
'(31 40 49 54 64 76 75 63)
'(45 58 59 61 70 62 64 62)))
(define-constant +q-chrominance-hi+
(2d-uint8-array '(11 11 15 29 62 62 62 62)
'(11 13 16 41 62 62 62 62)
'(15 16 35 62 62 62 62 62)
'(29 41 62 62 62 62 62 62)
'(62 62 62 62 62 62 62 62)
'(62 62 62 62 62 62 62 62)
'(62 62 62 62 62 62 62 62)
'(62 62 62 62 62 62 62 62)))
(defconstant +max-sample+ 255)
)
;;; Quantization performance test, each branch quantizes 30000 random matrixes
(eval-when (:compile-toplevel)
(defconstant +quantize-calibration-loops+ 30000)
(format t "Performing compile-time optimization.. please wait.~%")
(finish-output)
(defun qat1 ()
(loop for i fixnum from 1 to +quantize-calibration-loops+ do
(loop for row across +q-luminance+ do
(loop for q-coef fixnum across row
maximize (round (random 128) q-coef)))))
(defun qat2 ()
(loop for i fixnum from 1 to +quantize-calibration-loops+ do
(loop for q-row across +q-luminance+ do
(loop for val fixnum = (random 128)
for absval fixnum = (abs val)
for qc fixnum across q-row
maximize
(cond ((< absval (ash qc -1))
0)
((<= absval qc)
(if (minusp val)
-1
1))
((<= (ash absval -1) qc)
(if (zerop (logand absval 1))
(if (minusp val)
-1
1)
(if (minusp val)
-2
2)))
(t
(round val qc)))))))
(compile 'qat1)
(compile 'qat2)
(defvar *quantize-optimization*
(<= (let ((time1 (get-internal-run-time)))
(qat1)
(minus (get-internal-run-time) time1))
(let ((time1 (get-internal-run-time)))
(qat2)
(minus (get-internal-run-time) time1))))
(format t "Done.~%")
(finish-output))
(define-constant +q-tables+ (vector +q-luminance+ +q-chrominance+))
;;; This table is used to map coefficients into SSSS value
(define-constant +csize+ (make-array 2047
:initial-contents
(loop for i fixnum from 0 to 2046
collecting (integer-length (abs (minus i 1023))))))
;;; Some constants for colorspace mapper
(defconstant shift (1- (integer-length (ash most-positive-fixnum -7))))
(defconstant +.299+ (round (+ (* 0.299 (ash 1 shift)) 0.5)))
(defconstant +.587+ (round (+ (* 0.587 (ash 1 shift)) 0.5)))
(defconstant +.114+ (round (+ (* 0.114 (ash 1 shift)) 0.5)))
(defconstant +-.1687+ (round (+ (* -0.1687 (ash 1 shift)) 0.5)))
(defconstant +-.3313+ (round (+ (* -0.3313 (ash 1 shift)) 0.5)))
(defconstant +-.4187+ (round (+ (* -0.4187 (ash 1 shift)) 0.5)))
(defconstant +-.0813+ (round (+ (* -0.0813 (ash 1 shift)) 0.5)))
(defconstant +.5+ (round (+ (* 0.5 (ash 1 shift)) 0.5)))
(defconstant +uvoffset+ (ash 128 shift))
(defconstant +one-half+ (1- (ash 1 (1- shift))))
(defconstant +r-y-off+ 0)
(defconstant +g-y-off+ 256)
(defconstant +b-y-off+ (* 2 256))
(defconstant +r-u-off+ (* 3 256))
(defconstant +g-u-off+ (* 4 256))
(defconstant +b-u-off+ (* 5 256))
(defconstant +r-v-off+ +b-u-off+)
(defconstant +g-v-off+ (* 6 256))
(defconstant +b-v-off+ (* 7 256))
(declaim (type fixnum-array +ctab+ +cr-r-tab+ +cb-g-tab+ +cr-g-tab+ +cb-b-tab+))
;;;Direct color conversion table
(define-constant +ctab+
(let ((table (make-array 2048 :element-type 'fixnum :initial-element 0)))
(loop for i fixnum from 0 to 255 do
(setf (aref table (plus i +r-y-off+))
(mul +.299+ i))
(setf (aref table (plus i +g-y-off+))
(mul +.587+ i))
(setf (aref table (plus i +b-y-off+))
(mul +.114+ i))
(setf (aref table (plus i +r-u-off+))
(mul +-.1687+ i))
(setf (aref table (plus i +g-u-off+))
(mul +-.3313+ i))
(setf (aref table (plus i +b-u-off+))
(+ (mul +.5+ i) +uvoffset+ +one-half+))
(setf (aref table (plus i +r-v-off+))
(+ (mul +.5+ i) +uvoffset+ +one-half+))
(setf (aref table (plus i +g-v-off+))
(mul +-.4187+ i))
(setf (aref table (plus i +b-v-off+))
(mul +-.0813+ i)))
table))
;;; Constantsants for the inverse colorspace conversion
(defconstant +1.40200+ (round (+ (* 1.40200 (ash 1 shift)) 0.5)))
(defconstant +1.77200+ (round (+ (* 1.77200 (ash 1 shift)) 0.5)))
(defconstant +-0.71414+ (round (+ (* -0.71414 (ash 1 shift)) 0.5)))
(defconstant +-0.34414+ (round (+ (* -0.34414 (ash 1 shift)) 0.5)))
;;; Inverse color conversion tables
(define-constant +cr-r-tab+ (make-array 256
:element-type 'fixnum
:initial-contents
(loop for i from 0 to 255
for x from -127
collect (ash (plus (mul +1.40200+ x) +one-half+) (- shift)))))
(define-constant +cb-g-tab+ (make-array 256
:element-type 'fixnum
:initial-contents
(loop for i from 0 to 255
for x from -127
collect (plus (mul +-0.34414+ x) +one-half+))))
(define-constant +cr-g-tab+ (make-array 256
:element-type 'fixnum
:initial-contents
(loop for i from 0 to 255
for x from -127
collect (mul +-0.71414+ x))))
(define-constant +cb-b-tab+ (make-array 256
:element-type 'fixnum
:initial-contents
(loop for i from 0 to 255
for x from -127
collect (ash (plus (mul +1.77200+ x) +one-half+) (- shift)))))
;;; Constants for LLM DCT
(defconstant dct-shift ; defining DCT scaling
(if (<= (integer-length most-positive-fixnum) 31)
(minus 13 (round (minus 31 (integer-length most-positive-fixnum)) 2))
13))
(defconstant +shift-1+ (1- dct-shift))
(defconstant +shift+1+ (1+ dct-shift))
(defconstant +shift+4+ (+ dct-shift 4))
(defconstant +FIX-0-298631336+ (round (+ (* 0.298631336 (ash 1 dct-shift)) 0.5)))
(defconstant +FIX-0-390180644+ (round (+ (* 0.390180644 (ash 1 dct-shift)) 0.5)))
(defconstant +FIX-0-541196100+ (round (+ (* 0.541196100 (ash 1 dct-shift)) 0.5)))
(defconstant +FIX-0-765366865+ (round (+ (* 0.765366865 (ash 1 dct-shift)) 0.5)))
(defconstant +FIX-0-899976223+ (round (+ (* 0.899976223 (ash 1 dct-shift)) 0.5)))
(defconstant +FIX-1-175875602+ (round (+ (* 1.175875602 (ash 1 dct-shift)) 0.5)))
(defconstant +FIX-1-501321110+ (round (+ (* 1.501321110 (ash 1 dct-shift)) 0.5)))
(defconstant +FIX-1-847759065+ (round (+ (* 1.847759065 (ash 1 dct-shift)) 0.5)))
(defconstant +FIX-1-961570560+ (round (+ (* 1.961570560 (ash 1 dct-shift)) 0.5)))
(defconstant +FIX-2-053119869+ (round (+ (* 2.053119869 (ash 1 dct-shift)) 0.5)))
(defconstant +FIX-2-562915447+ (round (+ (* 2.562915447 (ash 1 dct-shift)) 0.5)))
(defconstant +FIX-3-072711026+ (round (+ (* 3.072711026 (ash 1 dct-shift)) 0.5)))
(declaim (type uint8-array *idct-limit-array*))
;;; Post-IDCT limiting array
(defvar *idct-limit-array* (make-array 512 :initial-element 0 :element-type 'uint8))
(loop for n from 0
for i from 128 to 383 do
(setf (aref *idct-limit-array* i) n))
(loop for i from 384 to 511 do
(setf (aref *idct-limit-array* i) 255))
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; Error conditions
(define-condition jpeg-error (error)
())
(define-condition jpeg-encoder-error (jpeg-error)
())
(define-condition internal-jpeg-encoder-error (jpeg-encoder-error)
()
(:report (lambda (condition stream)
(declare (ignorable condition))
(format stream "Internal error"))))
(define-condition illegal-number-of-components (jpeg-encoder-error)
()
(:report (lambda (condition stream)
(declare (ignorable condition))
(format stream "Illegal number of components specified"))))
(define-condition invalid-sampling-list (jpeg-encoder-error)
((components :reader components :initarg :ncomp))
(:report (lambda (condition stream)
(format stream "Wrong sampling list for ~D component(s)" (components condition)))))
(define-condition invalid-quantization-tables (jpeg-encoder-error)
()
(:report (lambda (condition stream)
(declare (ignorable condition))
(format stream "Too many quantization tables specified"))))
(define-condition invalid-q-factor (jpeg-encoder-error)
()
(:report (lambda (condition stream)
(declare (ignorable condition))
(format stream "Invalid Q factor!"))))
(define-condition invalid-sampling (jpeg-encoder-error)
()
(:report (lambda (condition stream)
(declare (ignorable condition))
(format stream "Invalid sampling specification!"))))
(define-condition jpeg-decoder-error (jpeg-error)
())
(define-condition unsupported-jpeg-frame-marker (jpeg-decoder-error)
()
(:report (lambda (condition stream)
(declare (ignorable condition))
(format stream "Unsupported marker in the frame header"))))
(define-condition unsupported-jpeg-format (jpeg-decoder-error)
((code :reader marker-code :initarg :code))
(:report (lambda (condition stream)
(format stream "Unsupported JPEG format: ~X" (marker-code condition)))))
(define-condition unrecognized-file-format (jpeg-decoder-error)
()
(:report (lambda (condition stream)
(declare (ignorable condition))
(format stream "Unrecognized JPEG format"))))
(define-condition invalid-buffer-supplied (jpeg-decoder-error)
((buffer :reader buffer :initarg :buffer))
(:report (lambda (condition stream)
(declare (ignorable condition))
(format stream "Invalid buffer supplied: ~A" (buffer condition)))))
(define-condition unsupported-arithmetic-encoding (jpeg-decoder-error)
()
(:report (lambda (condition stream)
(declare (ignorable condition))
(format stream "Arithmetic encoding not supported"))))
(define-condition unsupported-dnl-marker (jpeg-decoder-error)
()
(:report (lambda (condition stream)
(declare (ignorable condition))
(format stream "DNL marker is not supported"))))
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; Encoder part
;;; Subsamples inbuf into outbuf
(defun subsample (inbuf outbuf H V xlim ylim iH iV)
(declare #.*optimize*
(type fixnum H V xlim ylim iV iH)
(type sint16-2d-array inbuf)
(type (simple-array sint16-2d-array (*)) outbuf))
(loop for by fixnum from 0 below V do
(loop for bx fixnum from 0 below H
for block = (aref outbuf (plus bx (mul by H))) do
(loop for y fixnum from (the fixnum (ash by 3)) by iV
for yp fixnum from 0 to 7 do
(loop for x fixnum from (the fixnum (ash bx 3)) by iH
for xp fixnum from 0 to 7 do
(setf (s16ref block xp yp)
(the sint16 (cond ((and (<= x xlim) (<= y ylim))
(s16ref inbuf x y))
((and (> x xlim) (> y ylim))
(s16ref inbuf xlim ylim))
((> x xlim)
(s16ref inbuf xlim y))
((> y ylim)
(s16ref inbuf x ylim))
(t
(error 'internal-jpeg-encoder-error))
))))))))
;;; Returns sum of Vi*Hi
(defun count-relation (smp)
(loop for entry in smp
summing (mul (first entry) (second entry))))
;;; Cutting specified part of image (used for non-RGB images)
(defun crop-image (inbuf outbuf dx dy h w height width ncomp)
(let ((xend (plus dx (1- width)))
(yend (plus dy (1- height))))
(declare #.*optimize*
(type fixnum dx dy h w height width ncomp xend yend)
(type simple-array inbuf)
(type (simple-array sint16-2d-array (*)) outbuf))
(setf xend (min xend (1- w)))
(setf yend (min yend (1- h)))
(loop for yd fixnum from dy to yend
for ypos fixnum = (* w yd ncomp) do
(loop for xd fixnum from dx to xend
for pos fixnum = (plus (mul xd ncomp) ypos)
for cx fixnum = (minus xd dx)
for cy fixnum = (minus yd dy) do
(loop for i fixnum from 0 below ncomp do
(setf (s16ref (aref outbuf i) cx cy)
(minus (aref inbuf (plus pos i)) 128)))))
(values xend yend)))
;;; Direct color mapping
(defun colorspace-convert (RGB YUV dx dy h w height width)
(let ((xend (plus dx (1- width)))
(yend (plus dy (1- height)))
(Y (aref YUV 0))
(U (aref YUV 1))
(V (aref YUV 2)))
(declare #.*optimize*
(type fixnum dx dy h w height width xend yend)
(type sint16-2d-array Y U V)
(type fixnum-array +ctab+)
(type uint8-array RGB))
(setf xend (min xend (1- w)))
(setf yend (min yend (1- h)))
(loop for yd fixnum from dy to yend
for ypos fixnum = (mul3 w yd 3) do
(loop for xd fixnum from dx to xend
for pos fixnum = (plus (mul xd 3) ypos)
for r fixnum = (aref rgb (plus pos 2))
for g fixnum = (aref rgb (1+ pos))
for b fixnum = (aref rgb pos)
for cx fixnum = (minus xd dx)
for cy fixnum = (minus yd dy) do
(setf (s16ref Y cx cy) (minus (ash (the fixnum (+ (aref +ctab+ (plus r +r-y-off+))
(aref +ctab+ (plus g +g-y-off+))
(aref +ctab+ (plus b +b-y-off+))))
(- shift))
128))
(setf (s16ref U cx cy) (minus (ash (the fixnum (+ (aref +ctab+ (plus r +r-u-off+))
(aref +ctab+ (plus g +g-u-off+))
(aref +ctab+ (plus b +b-u-off+))))
(- shift))
128))
(setf (s16ref V cx cy) (minus (ash (the fixnum (+ (aref +ctab+ (plus r +r-v-off+))
(aref +ctab+ (plus g +g-v-off+))
(aref +ctab+ (plus b +b-v-off+))))
(- shift))
128))))
(values xend yend)))
;;; Converts given image sampling into frequencies of pixels of components
(defun convert-sampling (s Hmax Vmax)
(declare (type fixnum Hmax Vmax))
(make-array (length s)
:initial-contents (loop for entry in s
collecting (list (the fixnum (/ Hmax (first entry)))
(the fixnum (/ Vmax (second entry)))))))
;;; Quantization (also removes factor of 8 after DCT)
(defmacro quantize-block ()
(if *quantize-optimization*
'(loop for block-row across block
for q-row across q-table do
(loop for x fixnum from 0 to 7
for val fixnum = (ash (aref block-row x) -3)
for qc fixnum = (aref q-row x) do
(setf (aref block-row x) (the fixnum (round val qc)))))
'(loop for block-row across block
for q-row across q-table do
(loop for x fixnum from 0 to 7
for val fixnum = (ash (aref block-row x) -3)
for absval fixnum = (abs val)
for qc fixnum = (aref q-row x) do
(cond ((< absval (ash qc -1))
;; you won't believe, but under LWW 4.1 such ugly hack gives
;; very sufficient speedup
(setf (aref block-row x) 0))
((<= absval qc)
(if (minusp val)
(setf (aref block-row x) -1)
(setf (aref block-row x) 1)))
((<= (ash absval -1) qc)
(if (zerop (logand absval 1))
(if (minusp val)
(setf (aref block-row x) -1)
(setf (aref block-row x) 1))
(if (minusp val)
(setf (aref block-row x) -2)
(setf (aref block-row x) 2))))
(t
(setf (aref block-row x) (the fixnum (round val qc)))))))))
(defun quantize (block q-table)
(declare #.*optimize*
(type sint16-2d-array block)
(type uint8-2d-array q-table))
(quantize-block))
;;; LLM DCT aux definitions
(defun descale (x n)
(declare #.*optimize* (type fixnum x n))
(the fixnum (ash (plus x (ash 1 (1- n))) (- n))))
;;; Implementation of Loeffer, Ligtenberg and Moschytz forward DCT
(defun llm-dct (data)
(declare #.*optimize* (type sint16-2d-array data))
(loop with tmp0 fixnum and tmp1 fixnum and tmp2 fixnum
and tmp3 fixnum and tmp4 fixnum and tmp5 fixnum
and tmp6 fixnum and tmp7 fixnum and tmp10 fixnum
and tmp11 fixnum and tmp12 fixnum and tmp13 fixnum
and z1 fixnum and z2 fixnum and z3 fixnum
and z4 fixnum and z5 fixnum do
(loop for dptr across data do ; iterating over rows
(setf tmp0 (plus (aref dptr 0) (aref dptr 7)))
(setf tmp7 (minus (aref dptr 0) (aref dptr 7)))
(setf tmp1 (plus (aref dptr 1) (aref dptr 6)))
(setf tmp6 (minus (aref dptr 1) (aref dptr 6)))
(setf tmp2 (plus (aref dptr 2) (aref dptr 5)))
(setf tmp5 (minus (aref dptr 2) (aref dptr 5)))
(setf tmp3 (plus (aref dptr 3) (aref dptr 4)))
(setf tmp4 (minus (aref dptr 3) (aref dptr 4)))
(setf tmp10 (plus tmp0 tmp3))
(setf tmp13 (minus tmp0 tmp3))
(setf tmp11 (plus tmp1 tmp2))
(setf tmp12 (minus tmp1 tmp2))
(setf (aref dptr 0) (ash (plus tmp10 tmp11) 1))
(setf (aref dptr 4) (ash (minus tmp10 tmp11) 1))
(setf z1 (mul (plus tmp12 tmp13) +FIX-0-541196100+))
(setf (aref dptr 2) (descale (plus z1 (mul tmp13 +FIX-0-765366865+)) +shift-1+))
(setf (aref dptr 6) (descale (plus z1 (mul tmp12 (- +FIX-1-847759065+))) +shift-1+))
(setf z1 (plus tmp4 tmp7))
(setf z2 (plus tmp5 tmp6))
(setf z3 (plus tmp4 tmp6))
(setf z4 (plus tmp5 tmp7))
(setf z5 (mul (plus z3 z4) +FIX-1-175875602+))
(setf tmp4 (mul tmp4 +fix-0-298631336+))
(setf tmp5 (mul tmp5 +fix-2-053119869+))
(setf tmp6 (mul tmp6 +fix-3-072711026+))
(setf tmp7 (mul tmp7 +fix-1-501321110+))
(setf z1 (mul z1 (- +fix-0-899976223+)))
(setf z2 (mul z2 (- +fix-2-562915447+)))
(setf z3 (mul z3 (- +fix-1-961570560+)))
(setf z4 (mul z4 (- +fix-0-390180644+)))
(incf z3 z5)
(incf z4 z5)
(setf (aref dptr 7) (descale (plus3 tmp4 z1 z3) +shift-1+))
(setf (aref dptr 5) (descale (plus3 tmp5 z2 z4) +shift-1+))
(setf (aref dptr 3) (descale (plus3 tmp6 z2 z3) +shift-1+))
(setf (aref dptr 1) (descale (plus3 tmp7 z1 z4) +shift-1+)))
(loop for cnt fixnum from 7 downto 0 do ; second pass: on columns
(setf tmp0 (plus (s16ref data cnt 0) (s16ref data cnt 7)))
(setf tmp7 (minus (s16ref data cnt 0) (s16ref data cnt 7)))
(setf tmp1 (plus (s16ref data cnt 1) (s16ref data cnt 6)))
(setf tmp6 (minus (s16ref data cnt 1) (s16ref data cnt 6)))
(setf tmp2 (plus (s16ref data cnt 2) (s16ref data cnt 5)))
(setf tmp5 (minus (s16ref data cnt 2) (s16ref data cnt 5)))
(setf tmp3 (plus (s16ref data cnt 3) (s16ref data cnt 4)))
(setf tmp4 (minus (s16ref data cnt 3) (s16ref data cnt 4)))
(setf tmp10 (plus tmp0 tmp3))
(setf tmp13 (minus tmp0 tmp3))
(setf tmp11 (plus tmp1 tmp2))
(setf tmp12 (minus tmp1 tmp2))
(setf (s16ref data cnt 0) (descale (plus tmp10 tmp11) 1))
(setf (s16ref data cnt 4) (descale (minus tmp10 tmp11) 1))
(setf z1 (mul (plus tmp12 tmp13) +fix-0-541196100+))
(setf (s16ref data cnt 2) (descale (plus z1 (mul tmp13 +fix-0-765366865+)) +shift+1+))
(setf (s16ref data cnt 6) (descale (plus z1 (mul tmp12 (- +fix-1-847759065+))) +shift+1+))
(setf z1 (plus tmp4 tmp7))
(setf z2 (plus tmp5 tmp6))
(setf z3 (plus tmp4 tmp6))
(setf z4 (plus tmp5 tmp7))
(setf z5 (mul (plus z3 z4) +fix-1-175875602+))
(setf tmp4 (mul tmp4 +fix-0-298631336+))
(setf tmp5 (mul tmp5 +fix-2-053119869+))
(setf tmp6 (mul tmp6 +fix-3-072711026+))
(setf tmp7 (mul tmp7 +fix-1-501321110+))
(setf z1 (mul z1 (- +fix-0-899976223+)))
(setf z2 (mul z2 (- +fix-2-562915447+)))
(setf z3 (mul z3 (- +fix-1-961570560+)))
(setf z4 (mul z4 (- +fix-0-390180644+)))
(incf z3 z5)
(incf z4 z5)
(setf (s16ref data cnt 7) (descale (plus3 tmp4 z1 z3) +shift+1+))
(setf (s16ref data cnt 5) (descale (plus3 tmp5 z2 z4) +shift+1+))
(setf (s16ref data cnt 3) (descale (plus3 tmp6 z2 z3) +shift+1+))
(setf (s16ref data cnt 1) (descale (plus3 tmp7 z1 z4) +shift+1+)))
(return)))
;;; Forward DCT and quantization
(defun crunch (buf pos table)
(declare #.*optimize*
(type fixnum pos)
(type (simple-array sint16-2d-array (*)) buf))
(llm-dct (aref buf pos))
(quantize (aref buf pos) table))
;;; Q-tables scaling
(defun q-scale (table q-factor)
(declare #.*optimize*
(type uint8-2d-array table)
(type uint8 q-factor))
(when (/= q-factor 64)
(let ((factor (the uint8 (/ q-factor 64))))
(loop for q-row of-type uint8-array across table do
(loop for x fixnum from 0 to 7 do
(setf (aref q-row x)
(the fixnum (round (* (aref q-row x) factor)))))))))
;;; Function that maps value into SSSS
(defun csize (n)
(declare #.*optimize* (type fixnum n))
(aref +csize+ (plus n 1023)))
;;; zigzag ordering
(defun zigzag (buffer zz-result)
(declare #.*optimize*
(type sint16-2d-array buffer))
(loop for row of-type sint16-array across buffer
for z-row of-type uint8-array across +zigzag-index+ do
(loop for x fixnum from 0 to 7 do
(setf (aref zz-result (aref z-row x))
(the sint16 (aref row x)))))
zz-result)
(defun zigzag8 (buffer zz-result)
(declare #.*optimize*
(type uint8-2d-array buffer)
(type uint8-array zz-result))
(loop for row of-type uint8-array across buffer
for z-row of-type uint8-array across +zigzag-index+ do
(loop for x fixnum from 0 to 7 do
(setf (aref zz-result (aref z-row x))
(the fixnum (aref row x)))))
zz-result)
;;; Writes frame header
(defun write-frame-header (maxX maxY cn q-tables sampling tqv out-stream)
(declare #.*optimize* (type fixnum maxX maxY cn)
(type (simple-array uint8-2d-array (*)) q-tables)
;;(type uint8-array tqv)
)
(write-huffman-tables out-stream)
(write-quantization-tables q-tables out-stream)
;; writing frame header
(write-marker +M_SOF0+ out-stream)
(write-byte 0 out-stream) ; length
(write-byte (plus 8 (mul 3 cn)) out-stream)
(write-byte 8 out-stream) ; sample precision
(write-byte (ash maxY -8) out-stream) ; max height
(write-byte (logand maxY #xff) out-stream)
(write-byte (ash maxX -8) out-stream) ; max width
(write-byte (logand maxX #xff) out-stream)
(write-byte cn out-stream) ; number of components
(loop for entry in sampling
for i fixnum from 0 by 1 do
(write-byte i out-stream)
(write-byte ; H and V
(deposit-field (second entry) (byte 4 0)(ash (first entry) 4))
out-stream)
(write-byte (aref tqv i) out-stream))) ; Tq
;;; Writes byte with stuffing (adds zero after FF code)
(defun write-stuffed (b s)
(declare #.*optimize* (type uint8 b)
(type stream s))
(write-byte b s)
(if (= b #xFF)
(write-byte 0 s)))
;;; A function for bit streaming
;;; NB: probably it's a good idea to encapsulate this behavior into a class, but I'm
;;; afraid that method dispatch would be too slow
(defstruct (write-bits-state (:conc-name write-bits-))
(prev-byte 0 :type uint8)
(prev-length 0 :type fixnum))
(defun write-bits (bi ni s write-bits-state)
(declare #.*optimize*
(type fixnum bi ni)
(type stream s))
(loop with lim fixnum = (if (> ni 8) 1 0)
for i fixnum from lim downto 0 do
(let ((b (ldb (byte 8 (ash i 3)) bi))
(n (cond ((and (= i 1) (= ni 16)) 8)
((and (= i 0) (/= lim 0)) 8)
((= ni 8) 8)
(t (logand ni 7)))))
(declare (type fixnum b n)
(dynamic-extent b n))
(cond ((zerop n))
((>= (plus n (write-bits-prev-length write-bits-state)) 8)
(let* ((result (ash (write-bits-prev-byte write-bits-state)
(minus 8 (write-bits-prev-length write-bits-state))))
(total-length (plus n (write-bits-prev-length write-bits-state)))
(overflow (minus total-length 8)))
(declare (type fixnum overflow total-length result)
(dynamic-extent overflow total-length result))
(setf (write-bits-prev-byte write-bits-state) (ldb (byte overflow 0) b))
(write-stuffed (deposit-field
(ldb (byte (minus n overflow) overflow) b)
(byte (minus 8 (write-bits-prev-length write-bits-state)) 0)
result)
s)
(setf (write-bits-prev-length write-bits-state) overflow)))
(t (setf (write-bits-prev-byte write-bits-state)
(deposit-field b
(byte n 0)
(ash (write-bits-prev-byte write-bits-state) n)))
(incf (write-bits-prev-length write-bits-state) n))))))
;;; Encodes block using specified huffman tables, returns new pred (DC prediction value)
;;; and last code written to stream for padding
(defun encode-block (block tables pred s write-bits-state)
(declare #.*optimize* (type fixnum pred)
(type sint16-array block))
(let* ((ehufsi-dc (first (first tables)))
(ehufco-dc (second (first tables)))
(ehufsi-ac (first (second tables)))
(ehufco-ac (second (second tables)))
(newpred (aref block 0))
(diff (minus newpred pred))
(dcpos (csize diff)))
(declare (type fixnum pred newpred diff dcpos)
(type fixnum-array ehufco-ac ehufco-dc ehufsi-dc ehufsi-ac)
(dynamic-extent diff dcpos))
;; writing dc code first
(write-bits (aref ehufco-dc dcpos) (aref ehufsi-dc dcpos) s write-bits-state)
(cond ((minusp diff) (write-bits (1- diff) (csize diff) s write-bits-state))
(t (write-bits diff (csize diff) s write-bits-state)))
;; writing ac sequence
(loop with r fixnum = 0 for k fixnum from 1 to 63 do
(if (zerop (aref block k))
(if (= k 63)
(progn
(write-bits (aref ehufco-ac 0) (aref ehufsi-ac 0) s write-bits-state) ; writing EOB
(return))
(incf r))
(progn
(loop while (> r 15) do
(write-bits (aref ehufco-ac #xf0) (aref ehufsi-ac #xf0) s write-bits-state)
(decf r 16))
(let* ((ssss (csize (aref block k)))
(rs (plus ssss (ash r 4))))
(write-bits (aref ehufco-ac rs) (aref ehufsi-ac rs) s write-bits-state)
(when (minusp (aref block k))
(decf (aref block k) 1))
(write-bits (aref block k) ssss s write-bits-state))
(setf r 0))))
newpred))
;;; Emits q-tables
(defun write-quantization-tables (tables s)
(let ((len (plus 2 (mul 65 (length tables))))
(zz-result (make-array 64 :element-type 'uint8)))
(write-marker +M_DQT+ s)
(write-byte (ash len -8) s) ; MSB
(write-byte (logand len #xff) s) ; LSB
(loop for table across tables
for i fixnum from 0 do
(write-byte i s)
(write-sequence (zigzag8 table zz-result) s))))
;;; Emits huffman tables in the following order:
;;; luminance DC
;;; luminance AC
;;; chrominance DC
;;; chrominance AC
(defun write-huffman-tables (s)
(let ((len (+ 2 (* 17 4)
(length +luminance-dc-values+)
(length +luminance-ac-values+)
(length +chrominance-dc-values+)
(length +chrominance-ac-values+))))
(write-marker +M_DHT+ s)
(write-byte (ash len -8) s) ; MSB
(write-byte (logand len #xff) s) ; LSB
(write-hufftable +luminance-dc-bits+ +luminance-dc-values+ 0 s)
(write-hufftable +luminance-ac-bits+ +luminance-ac-values+ 16 s)
(write-hufftable +chrominance-dc-bits+ +chrominance-dc-values+ 1 s)
(write-hufftable +chrominance-ac-bits+ +chrominance-ac-values+ 17 s)))
;;; Writes single huffman table
(defun write-hufftable (bits vals tcti s)
(declare (type fixnum tcti))
(write-byte tcti s) ; Tc/Th
(write-sequence bits s)
(write-sequence vals s))
;;; Drops specified marker into the stream
(defun write-marker (code to)