diff options
Diffstat (limited to 'gnu/build/marionette.scm')
| -rw-r--r-- | gnu/build/marionette.scm | 67 |
1 files changed, 39 insertions, 28 deletions
diff --git a/gnu/build/marionette.scm b/gnu/build/marionette.scm index 24170bbd30..06b699bd7b 100644 --- a/gnu/build/marionette.scm +++ b/gnu/build/marionette.scm @@ -268,39 +268,50 @@ Monitor\")." ;; The "quit" command terminates QEMU immediately, with no output. (unless (string=? command "quit") (wait-for-monitor-prompt monitor))))) -(define* (marionette-screen-text marionette - #:key - (ocrad "ocrad")) - "Take a screenshot of MARIONETTE, perform optical character -recognition (OCR), and return the text read from the screen as a string. Do -this by invoking OCRAD (file name for GNU Ocrad's command)" - (define (random-file-name) - (string-append "/tmp/marionette-screenshot-" - (number->string (random (expt 2 32)) 16) - ".ppm")) - - (let ((image (random-file-name))) +(define* (invoke-ocrad-ocr image #:key (ocrad "ocrad")) + "Invoke the OCRAD command on image, and return the recognized text." + (let* ((pipe (open-pipe* OPEN_READ ocrad "-i" "-s" "10" image)) + (text (get-string-all pipe))) + (unless (zero? (close-pipe pipe)) + (error "'ocrad' failed" ocrad)) + text)) + +(define* (invoke-tesseract-ocr image #:key (tesseract "tesseract")) + "Invoke the TESSERACT command on IMAGE, and return the recognized text." + (let* ((output-basename (tmpnam)) + (output-basename* (string-append output-basename ".txt"))) (dynamic-wind (const #t) (lambda () - (marionette-control (string-append "screendump " image) - marionette) - - ;; Tell Ocrad to invert the image colors (make it black on white) and - ;; to scale the image up, which significantly improves the quality of - ;; the result. In spite of this, be aware that OCR confuses "y" and - ;; "V" and sometimes erroneously introduces white space. - (let* ((pipe (open-pipe* OPEN_READ ocrad - "-i" "-s" "10" image)) - (text (get-string-all pipe))) - (unless (zero? (close-pipe pipe)) - (error "'ocrad' failed" ocrad)) - text)) + (let ((exit-val (status:exit-val + (system* tesseract image output-basename)))) + (unless (zero? exit-val) + (error "'tesseract' failed" tesseract)) + (call-with-input-file output-basename* get-string-all))) (lambda () - (false-if-exception (delete-file image)))))) + (false-if-exception (delete-file output-basename)) + (false-if-exception (delete-file output-basename*)))))) + +(define* (marionette-screen-text marionette #:key (ocr "ocrad")) + "Take a screenshot of MARIONETTE, perform optical character +recognition (OCR), and return the text read from the screen as a string. Do +this by invoking OCR, which should be the file name of GNU Ocrad's +@command{ocrad} or Tesseract OCR's @command{tesseract} command." + (define image (string-append (tmpnam) ".ppm")) + ;; Use the QEMU Monitor to save an image of the screen to the host. + (marionette-control (string-append "screendump " image) marionette) + ;; Process it via the OCR. + (cond + ((string-contains ocr "ocrad") + (invoke-ocrad-ocr image #:ocrad ocr)) + ((string-contains ocr "tesseract") + (invoke-tesseract-ocr image #:tesseract ocr)) + (else (error "unsupported ocr command")))) (define* (wait-for-screen-text marionette predicate - #:key (timeout 30) (ocrad "ocrad")) + #:key + (ocr "ocrad") + (timeout 30)) "Wait for TIMEOUT seconds or until the screen text on MARIONETTE matches PREDICATE, whichever comes first. Raise an error when TIMEOUT is exceeded." (define start @@ -312,7 +323,7 @@ PREDICATE, whichever comes first. Raise an error when TIMEOUT is exceeded." (let loop ((last-text #f)) (if (> (car (gettimeofday)) end) (error "'wait-for-screen-text' timeout" 'ocr-text: last-text) - (let ((text (marionette-screen-text marionette #:ocrad ocrad))) + (let ((text (marionette-screen-text marionette #:ocr ocr))) (or (predicate text) (begin (sleep 1) |