Implements an image recognition captcha.

"; break; case 'admin/modules#description': case 'admin/modules/textimage': case 'admin/textimage': $output = t('Implements an image recognition captcha.'); break; } return $output; } function textimage_captchachallenge(&$form) { $form['captcha_response'] = array ( '#type' => 'textfield', '#title' => t('Captcha Validation'), '#default_value' => '', '#required' => TRUE, '#validate' => array('_captcha_validate' => array()), '#description' => t('Please type in the letters/numbers that are shown in the image above.'), '#prefix' => 'Captcha Image: you will need to recognize the text in it.', ); return $form; } function textimage_captchavalidate(&$captcha_word, &$correct) { $captcha_word = drupal_strtolower($captcha_word); if (($_SESSION['captcha'] != '') && $captcha_word == $_SESSION['captcha']) { $correct = true; } else { $correct = false; form_set_error('captcha_response', t('The image verification code you entered is incorrect.')); } } /** * Implementation of hook_menu(). */ function textimage_menu($may_cache) { $items = array(); $suffix = ''; if (arg(2)!=null) $suffix='/'.arg(2); $items[] = array( 'path' => '_textimage/image'.$suffix, 'title' => t('textimage'), 'callback' => '_textimage_image', 'access' => user_access('access textimages'), 'type' => MENU_CALLBACK ); return $items; } function textimage_perm() { return array('access textimages'); } function textimage_settings() { $fonts_path = variable_get("textimage_fonts_path", ""); $images_path = variable_get("textimage_images_path", ""); //check for GD if (!function_exists(imagecreate)) drupal_set_message(t('Image library not available. Textimage needs the GD library extension to be installed. Please install GD.')); //check for TTF support elseif (!function_exists(imagettftext)) drupal_set_message(t('Your image library does not seem to have TrueType font support. Textimage will work, but will use the default inbuilt font.'),'status'); //check for valid font path elseif ($fonts_path!="" && !is_dir($fonts_path)) drupal_set_message(t('The current font path is invalid. The default font will be used.')); //check for valid image path if ($images_path!="" && !is_dir($images_path)) drupal_set_message(t('The current images path is invalid. No images will be used.')); //Fonts settings $form['fonts'] = array( '#type' => 'fieldset', '#title' => t('Fonts settings'), '#collapsible' => TRUE, '#collapsed' => FALSE ); $form['fonts']['textimage_use_only_upper'] = array( '#type' => 'checkbox', '#title' => t('Use only Uppercase'), '#default_value' => variable_get('textimage_use_only_upper',0) ); $form['fonts']['textimage_fonts_path'] = array( '#type' => 'textfield', '#title' => t('TrueType Fonts Path'), '#default_value' => $fonts_path, '#size' => 30, '#maxlength' => 255, '#description' => t('Location of the directory where the Truetype (.ttf) fonts are stored. If you do not provide any fonts, the module will use the default font for text. Relative paths will be resolved relative to the Drupal installation directory.'), ); $form['fonts']['textimage_font_size'] = array( '#type' => 'textfield', '#title' => t('Font Size'), '#default_value' => variable_get('textimage_font_size',24), '#size' => 5, '#maxlength' => 2, '#description' => t('Font size of Captcha text (in pixels).'), '#validate' => array("_textimage_number_validate" => array("textimage_font_size")), ); $form['fonts']['textimage_char_spacing_max'] = array( '#type' => 'textfield', '#title' => t('Character Spacing'), '#default_value' => variable_get('textimage_char_spacing_max',10), '#size' => 5, '#maxlength' => 4, '#description' => t('Sets the kerning between letters in Captcha. Higher numbers indicate more spacing.'), '#validate' => array("_textimage_number_validate" => array("textimage_char_spacing_max")), ); $form['fonts']['textimage_char_jiggle_amount'] = array( '#type' => 'textfield', '#title' => t('Character Jiggle'), '#default_value' => variable_get('textimage_char_jiggle_amount',5), '#size' => 5, '#maxlength' => 2, '#description' => t('Sets the amount of up and down movement in the Captcha letters. Higher numbers indicate more jiggling.'), '#validate' => array("_textimage_number_validate" => array("textimage_char_jiggle_amount")), ); $form['fonts']['textimage_char_rotate_amount'] = array( '#type' => 'textfield', '#title' => t('Character Rotation'), '#default_value' => variable_get('textimage_char_rotate_amount',5), '#size' => 5, '#maxlength' => 2, '#description' => t('Sets the amount of rotation in the Captcha letters (in degrees, only works with non-default fonts).'), '#validate' => array("_textimage_number_validate" => array("textimage_char_rotate_amount")), ); $form['fonts']['textimage_char_size_amount'] = array( '#type' => 'textfield', '#title' => t('Character Size Adjustment'), '#default_value' => variable_get('textimage_char_size_amount',2), '#size' => 5, '#maxlength' => 2, '#description' => t('Sets the amount of variation in size between the different letters in the Captcha (in pixels).'), '#validate' => array("_textimage_number_validate" => array("textimage_char_size_amount")), ); //Image settings $form['images'] = array( '#type' => 'fieldset', '#title' => t('Image settings'), '#collapsible' => TRUE, '#collapsed' => FALSE ); $form['images']['textimage_images_path'] = array( '#type' => 'textfield', '#title' => t('Background Images Path'), '#default_value' => $images_path, '#size' => 30, '#maxlength' => 255, '#description' => t('Location of the directory where the background images are stored. If you do not provide a directory, solid colors will be used. Relative paths will be resolved relative to the Drupal installation directory.'), ); $form['images']['textimage_image_noise'] = array( '#type' => 'textfield', '#title' => t('Image Noise (pixels)'), '#default_value' => variable_get('textimage_image_noise',4), '#size' => 5, '#maxlength' => 4, '#description' => t('Sets the amount of noise (random pixels) in the Captcha image. Higher numbers indicate more noise.'), '#validate' => array("_textimage_number_validate" => array("textimage_image_noise")), ); $form['images']['textimage_image_lines'] = array( '#type' => 'textfield', '#title' => t('Image Noise (lines)'), '#default_value' => variable_get('textimage_image_lines',4), '#size' => 5, '#maxlength' => 4, '#description' => t('Sets the amount of noise (random lines) in the Captcha image. Higher numbers indicate more noise.'), '#validate' => array("_textimage_number_validate" => array("textimage_image_lines")), ); $form['images']['textimage_image_margin'] = array( '#type' => 'textfield', '#title' => t('Image Margin'), '#default_value' => variable_get('textimage_image_margin',10), '#size' => 5, '#maxlength' => 4, '#description' => t('Set a distance between the Captcha letters and the edges of the image.'), '#validate' => array("_textimage_number_validate" => array("textimage_image_margin")), ); $form['info'] = array( '#type' => 'fieldset', '#title' => t('Image and font information'), '#collapsible' => TRUE, '#collapsed' => FALSE ); if (isset($fonts_path)) { $imagefontinfo .= t('Number of fonts found: ').count(_textimage_font_list()); } if (isset($images_path)) { $imagefontinfo .= '
'.t('Number of background images found: ').count(_textimage_image_list()); } $gdinfo = gd_info(); $imagefontinfo .= '
'.t('GD Version: ').$gdinfo["GD Version"]; $imagefontinfo .= '
'.t(' FreeType Support: '); $imagefontinfo .= ($gdinfo["FreeType Support"]==true) ? 'True' : 'False'; $imagefontinfo .= '
'; $form['info']['captcha_info'] = array ( '#type' => 'item', '#value' => $imagefontinfo, ); return $form; } function textimage_settings_form_validate ($form_id,$form) { //check for valid font path if ($form['textimage_fonts_path'] !="" && !is_dir($form['textimage_fonts_path'])) form_set_error('textimage_fonts_path', t('The entered font path is invalid')); //check for valid image path if ($form['textimage_images_path'] !="" && !is_dir($form['textimage_images_path'])) form_set_error('textimage_images_path', t('The entered image path is invalid')); } function _textimage_number_validate ($field,$fieldName) { if (!is_numeric($field['#value'])) { form_set_error($fieldName,t("The value for")." ".t($field['#title'])." ".t("must be a number")); } } /** * Prints an image containing a textimage code. */ function _textimage_image() { //if we don't have GD2 functions, we can't generate the image if (!function_exists('imagecreatetruecolor')) return; // Set headers header('Expires: Mon, 01 Jan 1997 05:00:00 GMT'); header('Cache-Control: no-store, no-cache, must-revalidate'); header('Cache-Control: post-check=0, pre-check=0', false); header('Pragma: no-cache'); header('Content-type: image/png'); $string = _textimage_code(); // Get truetype font list $fonts = _textimage_font_list(); // Get the background images list $images = _textimage_image_list(); // Randomization amounts: $charSpacingMax = variable_get('textimage_char_spacing_max',10); // Letter spacing max (pixels) $charSpacingMin = max($charSpacingMax*.5,0); // Letter spacing minimum (pixels) $charJiggleAmount = variable_get('textimage_char_jiggle_amount',5); // Up and down randomization (pixels) $charRotateAmount = variable_get('textimage_char_rotate_amount',5); // Character rotation amount (degrees) $charSizeAmount = variable_get('textimage_char_size_amount',2); // Character size amount (pixels) $imageRotateAmount = variable_get('captcha_image_rotate_amount',12); // Image rotation amount (degrees) // Static amounts: $charInitialSize = variable_get('textimage_font_size',24); // Initial Font $imageNoise = variable_get('textimage_image_noise',4); // Amount of noise added to image $imageLines = variable_get('textimage_image_lines',4); // Amount of noise added to image $imageMargin = variable_get('textimage_image_margin',10); // Margin around image (pixels) // write text using a truetype font if (function_exists(imagettftext) && count($fonts) > 0) { // Initialize variables for the loop $characterDetails = array(); // contains the final info about each character // Build a list of character settings for the captcha string for ($i=0;$i $charSize, "angle" => $charAngle, "x" => $x, "y" => $y, "color" => $foreground, "font" => $font, "char" => $char ); // Increment the image size $imageWidth = $x + $charWidth; $imageHeight = max($imageHeight,$y+$charJiggleAmount); } // Create the image based off the string length and margin if (count($images) > 0) { // We're going to be using an image, and need a tranparent background to start with $im = _textimage_create_transparent_image($imageWidth+2*$imageMargin, $imageHeight+2*$imageMargin); $noisecolor = imagecolorallocatealpha($im, 0, 0, 0, 127); } else { // Just make a plain-jane color brackground $im = imagecreatetruecolor($imageWidth+2*$imageMargin, $imageHeight+2*$imageMargin); $background = imagecolorallocate($im, rand(180, 250), rand(180, 250), rand(180, 250)); $noisecolor = $background; imagefill($im, 0, 0, $background); } // Specify colors to be used in the image $foreground = imagecolorallocate($im, rand(0, 80), rand(0, 80), rand(0, 80)); foreach($characterDetails as $char) { // draw character imagettftext($im,$char['size'],$char['angle'],$char['x']+$imageMargin,$char['y']+$imageMargin,$foreground,$char['font'],$char['char']); } } else { // write text using a built-in font $x = 0; $y = 0; $imageWidth = 60 + drupal_strlen($string)*$charSpacingMax*.35; $imageHeight = 30 + $charJiggleAmount; // Create the image if (count($images) > 0 && function_exists(imagecolorallocatealpha)) { // We're going to be using an image, and need a tranparent background to start with $im = _textimage_create_transparent_image($imageWidth, $imageHeight); $noisecolor = imagecolorallocatealpha($im, 0, 0, 0, 127); } else { // Just make a plain-jane color brackground $im = imagecreatetruecolor($imageWidth, $imageHeight); $background = imagecolorallocate($im, rand(180, 250), rand(180, 250), rand(180, 250)); $noisecolor = $background; imagefill($im, 0, 0, $background); } // Add the text for ($i=0;$i 0) { // Prepare a larger image with a background image $im2 = _textimage_create_transparent_image($imageWidth, $imageHeight); } else { // Prepare a larger image with a solid color $im2 = imagecreatetruecolor($imageWidth, $imageHeight); imagefill($im2, 0, 0, $background); } $result = imagecopyresampled ($im2, $im, $imageMargin, $imageMargin, 0, 0, $imageWidth, $imageHeight, imagesx($im), imagesy($im)); $im = $im2; } // strikethrough imageline($im, rand(0, 120), rand(0, 120), rand(0, 120), rand(0, 120), $foreground); // Add Noise for ($x=0; $x<$imageWidth; $x++) { for ($row=0; $row<$imageNoise;$row++) { $y = rand(0,$imageHeight); imagesetpixel($im, $x, $y, $noisecolor); } } // Add Lines and Ellipses for ($x=0; $x<$imageLines;$x++) { imageline($im, rand(0, $imageWidth), rand(0, $imageHeight), rand(0, $imageWidth), rand(0, $imageHeight), $noisecolor); imageellipse($im, rand(0, $imageWidth), rand(0, $imageHeight), rand(0, $imageWidth), rand(0, $imageHeight), $noisecolor); } // Fill image with a random background image if available if (count($images) > 0) { $image = $images[rand(0,count($images)-1)]; _textimage_apply_background_image($im,$image); } //output to browser imagepng($im); imagedestroy($im); } /** * Returns a random string for use in a captcha */ function _textimage_code() { $consts='bcdgjxvmnprst'; $vowels='aeiou'; for ($x=0; $x < 6; $x++) { mt_srand ((double) microtime() * 1000000); $const[$x] = drupal_substr($consts,mt_rand(0,drupal_strlen($consts)-1),1); $vow[$x] = drupal_substr($vowels,mt_rand(0,drupal_strlen($vowels)-1),1); } $string = $const[0] . $vow[0] .$const[2] . $const[1] . $vow[1] . $const[3] . $vow[3] . $const[4]; $string = drupal_substr($string,0,rand(4,6)); //everytime we create a new code, we write it to session $_SESSION['captcha'] = drupal_strtolower($string); if(variable_get('textimage_use_only_upper',0)) $string = drupal_strtoupper($string); return $string; } /** * Returns an array of files with TTF extensions in the specified directory. */ function _textimage_font_list() { $fontdir = variable_get("textimage_fonts_path", ""); $filelist = array(); if (is_dir($fontdir) && $handle = opendir($fontdir)) { while ($file = readdir($handle)) { if (preg_match("/\.ttf$/i",$file) == 1) $filelist[] = $fontdir.'/'.$file; } closedir($handle); } return $filelist; } /** * Returns an array of files with jpg, png, and gif extensions in the specified directory. */ function _textimage_image_list() { $imagesdir = variable_get("textimage_images_path", ""); $filelist = array(); if (is_dir($imagesdir) && $handle = opendir($imagesdir)) { while ($file = readdir($handle)) { if (preg_match("/\.gif|\.png|\.jpg$/i",$file) == 1) $filelist[] = $imagesdir.'/'.$file; } closedir($handle); } return $filelist; } /** * Overlays an image to the supplied image resource */ function _textimage_apply_background_image (&$imageResource,$imageFile) { $backgroundResource = image_gd_open($imageFile,substr($imageFile,-3)); // Copy the text onto the background $backX = imagesx($backgroundResource); $backY = imagesy($backgroundResource); $textX = imagesx($imageResource); $textY = imagesy($imageResource); $randomBackX = rand(0,$backX-$textX); $randomBackY = rand(0,$backY-$textY); // Place the text onto a random location of the background image imagecopyresampled($backgroundResource,$imageResource,$randomBackX,$randomBackY,0,0,$textX,$textY,$textX,$textY); // Crop the background image to the original image size imagecopyresampled($imageResource,$backgroundResource,0,0,$randomBackX,$randomBackY,$textX,$textY,$textX,$textY); } /** * Creates transparent image resources for images with graphic backgrounds */ function _textimage_create_transparent_image($x, $y) { $i = imagecreatetruecolor($x, $y); $b = imagecreatefromstring(base64_decode(_text_image_blankpng())); imagealphablending($i, false); imagesavealpha($i, true); imagecopyresized($i, $b ,0 ,0 ,0 ,0 ,$x, $y, imagesx($b), imagesy($b)); return $i; } function _text_image_blankpng() { $c = "iVBORw0KGgoAAAANSUhEUgAAACgAAAAoCAYAAACM/rhtAAAABGdBTUEAAK/INwWK6QAAABl0RVh0U29m"; $c .= "dHdhcmUAQWRvYmUgSW1hZ2VSZWFkeXHJZTwAAADqSURBVHjaYvz//z/DYAYAAcTEMMgBQAANegcCBNCg"; $c .= "dyBAAA16BwIE0KB3IEAADXoHAgTQoHcgQAANegcCBNCgdyBAAA16BwIE0KB3IEAADXoHAgTQoHcgQAAN"; $c .= "egcCBNCgdyBAAA16BwIE0KB3IEAADXoHAgTQoHcgQAANegcCBNCgdyBAAA16BwIE0KB3IEAADXoHAgTQ"; $c .= "oHcgQAANegcCBNCgdyBAAA16BwIE0KB3IEAADXoHAgTQoHcgQAANegcCBNCgdyBAAA16BwIE0KB3IEAA"; $c .= "DXoHAgTQoHcgQAANegcCBNCgdyBAgAEAMpcDTTQWJVEAAAAASUVORK5CYII="; return $c; } ?> Stylistic Tendencies in the XIX Century Russian Book Art | Odesskiy Listok

Stylistic Tendencies in the XIX Century Russian Book Art

Russian 19-century non-religious book design and illustrative art belongs to the periphery of contemporary European book art. The achievements of Russian book art were performed in the mainstream of artistic tendencies that originated in France, Holland, England and Germany. Starting from Peter the Great reign until the middle of 19-century Russia imported type sets and used politypes drawn by the European masters.

“There is a tendency to assimilate the western culture in the editions of the time. However, the second- sort quality western editions were often accepted as an example” – wrote a famous scientist A.A.Sidorov in 1946. The word combination reflects conflicting tendencies of the Soviet times. On one hand, an honest scientist had to admit an obvious truth. On the other hand, a captive of totalitarian regime placed in the middle of a constant struggle with western cosmopolitan cultural values had to, in order to survive, denigrate “the detrimental influence of the West”. It is possible to admit that almost all the research on Russian culture of the New Times is consciously or unconsciously distorted by the above contradiction. Russian reader was used to Esopian language and could read between the lines to find a grain of truth. However, it becomes difficult for a foreigner to make any sense of the articles and monographs of the Soviet Times.

While working on an article preceding “The Catalog of illustrated Editions of 1870 – 1899” I would like to offer more transparent interpretation of Russian 19-century book history.

Original list was created during my work on a thesis dedicated to the interpretation of the classical literature in graphic art. Lacking a systematic description of illustrated editions since 1870 made it necessary to create a catalog. The catalogs of the major publishing houses covered a period starting around 1870-s and ending at 1890-s. Most of these books and albums served as a material for critical analysis. Work on the Catalog was continued when I was invited to participate in a 6-volume edition monograph “The Russian Book” It was produced by the Division of bibliography of the National Russian Library in St-Petersburg.

Articles in “The Russian Book” dedicated to the design and book illustration of the second half of the 19-century were difficult for the researcher. The book art became an object of study in Russia only in 1890-s.

Descriptions of the illustrated books covered only up to 1860-s. At the turn of the century all the major publishing houses were already producing catalogs.

Period between the 1870-s and the 1890-s was out of scope of the researchers.

Later on for more than 50 years no objective evaluation of this period in Russian book art was created. No single major researcher existed. Common opinion was that the material has not worth a serious study. Book art of the second half of the 19th century was evaluated by using the inappropriate criteria.

Being a product of various stylistic tendencies in a complicated dynamic fusion Russian book of 19th-century was in constant transition. The elements, however, formed a system that had structural entity. New organizational principles were used to supply the unity of the material.

My aspiration to see the process in all its complexity is dictated primarily by my desire to comprehend an artistic logic of the period. Russian art with all its complexity forms a unified artistic system. It is difficult to study so far as it forms by interaction of many contracting and even mutually exclusive elements and principles. The form and content do not come to the harmonious fusion. Such a system of organizing an artistic material was breaking the existing traditions of the book art and formed a new book media.

Our comprehension of “eclectic media” while reading and looking through the book results in a combination of spatially differentiated asynchronous impressions. The result is determined by material nature of the book. The book is a Thing. However, it is also an Idea expressed in words. The two qualities constantly interact one with another as a material and virtual spaces.

The second half of 19-century book media was forming stochastically. Only at the turn of the century in Russia we can talk of consciously organized interaction of elements in the process. The eclectic system was a dynamic equilibrium of contrasting principles applied to form an illustrated book. The unity of clearly expressed, easily comprehended and sometimes even superficial qualities was intuitively associated with the word and content.

It was a way to crystallize a new book form built on organic principles.

In Russia of the early 20-century in parallel with revolutionary transformation of mind a new form of book was created. New avant-garde art of futurism and subsequent constructivism made it possible. It was a new book, an unprecedented thing defined by its functions in communication and information exchange.

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