Read image IPTC data - image

I'm having some trouble with reading out the IPTC data of some images, the reason why I want to do this, is because my client has all the keywords already in the IPTC data and doesn't want to re-enter them on the site.
So I created this simple script to read them out:
$size = getimagesize($image, $info);
if(isset($info['APP13'])) {
$iptc = iptcparse($info['APP13']);
print '<pre>';
var_dump($iptc['2#025']);
print '</pre>';
}
This works perfectly in most cases, but it's having trouble with some images.
Notice: Undefined index: 2#025
While I can clearly see the keywords in photoshop.
Are there any decent small libraries that could read the keywords in every image? Or am I doing something wrong here?

I've seen a lot of weird IPTC problems. Could be that you have 2 APP13 segments. I noticed that, for some reasons, some JPEGs have multiple IPTC blocks. It's possibly the problem with using several photo-editing programs or some manual file manipulation.
Could be that PHP is trying to read the empty APP13 or even embedded "thumbnail metadata".
Could be also problem with segments lenght - APP13 or 8BIM have lenght marker bytes that might have wrong values.
Try HEX editor and check the file "manually".

I have found that IPTC is almost always embedded as xml using the XMP format, and is often not in the APP13 slot. You can sometimes get the IPTC info by using iptcparse($info['APP1']), but the most reliable way to get it without a third party library is to simply search through the image file from the relevant xml string (I got this from another answer, but I haven't been able to find it, otherwise I would link!):
The xml for the keywords always has the form "<dc:subject>...<rdf:Seq><rdf:li>Keyword 1</rdf:li><rdf:li>Keyword 2</rdf:li>...<rdf:li>Keyword N</rdf:li></rdf:Seq>...</dc:subject>"
So you can just get the file as a string using file_get_contents(get_attached_file($attachment_id)), use strpos() to find each opening (<rdf:li>) and closing (</rdf:li>) XML tag, and grab the keyword between them using substr().
The following snippet works for all jpegs I have tested it on. It will fill the array $keys with IPTC tags taken from an image on wordpress with id $attachment_id:
$content = file_get_contents(get_attached_file($attachment_id));
// Look for xmp data: xml tag "dc:subject" is where keywords are stored
$xmp_data_start = strpos($content, '<dc:subject>') + 12;
// Only proceed if able to find dc:subject tag
if ($xmp_data_start != FALSE) {
$xmp_data_end = strpos($content, '</dc:subject>');
$xmp_data_length = $xmp_data_end - $xmp_data_start;
$xmp_data = substr($content, $xmp_data_start, $xmp_data_length);
// Look for tag "rdf:Seq" where individual keywords are listed
$key_data_start = strpos($xmp_data, '<rdf:Seq>') + 9;
// Only proceed if able to find rdf:Seq tag
if ($key_data_start != FALSE) {
$key_data_end = strpos($xmp_data, '</rdf:Seq>');
$key_data_length = $key_data_end - $key_data_start;
$key_data = substr($xmp_data, $key_data_start, $key_data_length);
// $ctr will track position of each <rdf:li> tag, starting with first
$ctr = strpos($key_data, '<rdf:li>');
// Initialize empty array to store keywords
$keys = Array();
// While loop stores each keyword and searches for next xml keyword tag
while($ctr != FALSE && $ctr < $key_data_length) {
// Skip past the tag to get the keyword itself
$key_begin = $ctr + 8;
// Keyword ends where closing tag begins
$key_end = strpos($key_data, '</rdf:li>', $key_begin);
// Make sure keyword has a closing tag
if ($key_end == FALSE) break;
// Make sure keyword is not too long (not sure what WP can handle)
$key_length = $key_end - $key_begin;
$key_length = (100 < $key_length ? 100 : $key_length);
// Add keyword to keyword array
array_push($keys, substr($key_data, $key_begin, $key_length));
// Find next keyword open tag
$ctr = strpos($key_data, '<rdf:li>', $key_end);
}
}
}
I have this implemented in a plugin to put IPTC keywords into WP's "Description" field, which you can find here.

ExifTool is very robust if you can shell out to that (from PHP it looks like?)

Related

Get TIFF tag value (including non-ASCII characters) from TIFF images in Java 11

I am trying to read different tag values (like tags 259 (Compression), 33432 (Copyright), 306 (DateTime), 315 (Artist) etc.) from a TIFF image in Java. Can anyone suggest what is best way to get those values in Java 11 ?
i tried to get those values using tiffinfo commands (like "tiffinfo -c myfile.tif"). But i did not find any specific command in tiffinfo (libtiff) or any Java library which will give me the specific tag values (e.g. DateTime) of a TIFF image.
Update:
As haraldK suggested, i tried with ImageIO like following
try (ImageInputStream input = ImageIO.createImageInputStream(tiffFile)) {
ImageReader reader = ImageIO.getImageReaders(input).next(); // TODO: Handle reader not found
reader.setInput(input);
IIOMetadata metadata = reader.getImageMetadata(0);
TIFFDirectory ifd = TIFFDirectory.createFromMetadata​(metadata);
TIFFField dateTime = ifd.get​TIFFField(306);
String dateString = dateTime.getAsString(0);
}
But it does not give exact value of the tag. In case of non-ASCII value (ö, ü, ä etc), question marks replace the real values.
Can anyone tell me how to get the exact value (including non-ASCII) of the tag from TIFFField ?
You can use standard ImageIO, read the TIFF image metadata and get the requested values from it, like this by using some extra support classes in the JDK, starting from Java 9:
try (ImageInputStream input = ImageIO.createImageInputStream(tiffFile)) {
ImageReader reader = ImageIO.getImageReaders(input).next(); // TODO: Handle reader not found
reader.setInput(input);
IIOMetadata metadata = reader.getImageMetadata(0); // 0 is the index of first image
TIFFDirectory ifd = TIFFDirectory.createFromMetadata​(metadata);
TIFFField dateTime = ifd.get​TIFFField(306); // Yes, that's 3 F's...
String dateString = dateTime.getAsString(0); // TIFF dates are strings...
}
tiffFile must be a valid (existing, readable) java.io.File, java.io.RandomAccessFile or java.io.InputStream (or other supported input, this is plugin-based, really). If not, input will be null, and the code will fail.
You can use similar, but a lot more verbose version, that will work in older versions of Java, as long as you have a TIFF plugin:
try (ImageInputStream input = ImageIO.createImageInputStream(tiffFile)) {
ImageReader reader = ImageIO.getImageReaders(input).next(); // TODO: Handle reader not found
reader.setInput(input);
IIOMetadata metadata = reader.getImageMetadata(0); // 0 is the index of first image
// Get "native" TIFF metadata for first IFD
IIOMetadataNode root = metadata.getAsTree("com_sun_media_imageio_plugins_tiff_image_1.0");
Node ifd = root.getFirstChild();
NodeList fields = ifd.getElementsByTagName("TIFFField"); // Yes, that's 3 F's...
for (int i = 0; i < fields.getLength(); i++) {
Element field = (Element) fields.item(i);
if ("306".equals(field.getAttribute("number"))) {
// This is your DateTime (306) tag,
// now do something with it 😀
// ...
}
}
}
Hardly elegant code, though... The Java 9+ approach is much cleaner and easier to reason about.

Any ar js multimarkers learning tutorial?

I have been searching for ar.js multimarkers tutorial or anything that explains about it. But all I can find is 2 examples, but no tutorials or explanations.
So far, I understand that it requires to learn the pattern or order of the markers, then it stores it in localStorage. This data is used later to display the image.
What I don't understand, is how this "learner" is implemented. Also, the learning process is only used once by the "creator", right? The output file should be stored and then served later when needed, not created from scratch at each person's phone or computer.
Any help is appreciated.
Since the question is mostly about the learner page, I'll try to break it down as much as i can:
1) You need to have an array of {type, URL} objects.
A sample of creating the default array is shown below (source code):
var markersControlsParameters = [
{
type : 'pattern',
patternUrl : 'examples/marker-training/examples/pattern-files/pattern-hiro.patt',
},
{
type : 'pattern',
patternUrl : 'examples/marker-training/examples/pattern-files/pattern-kanji.patt',
}]
2) You need to feed this to the 'learner' object.
By default the above object is being encoded into the url (source) and then decoded by the learner site. What is important, happens on the site:
for each object in the array, an ArMarkerControls object is created and stored:
// array.forEach(function(markerParams){
var markerRoot = new THREE.Group()
scene.add(markerRoot)
// create markerControls for our markerRoot
var markerControls = new THREEx.ArMarkerControls(arToolkitContext, markerRoot, markerParams)
subMarkersControls.push(markerControls)
The subMarkersControls is used to create the object used to do the learning. At long last:
var multiMarkerLearning = new THREEx.ArMultiMakersLearning(arToolkitContext, subMarkersControls)
The example learner site has multiple utility functions, but as far as i know, the most important here are the ArMultiMakersLearning members which can be used in the following order (or any other):
// this method resets previously collected statistics
multiMarkerLearning.resetStats()
// this member flag enables data collection
multiMarkerLearning.enabled = true
// this member flag stops data collection
multiMarkerLearning.enabled = false
// To obtain the 'learned' data, simply call .toJSON()
var jsonString = multiMarkerLearning.toJSON()
Thats all. If you store the jsonString as
localStorage.setItem('ARjsMultiMarkerFile', jsonString);
then it will be used as the default multimarker file later on. If you want a custom name or more areas - then you'll have to modify the name in the source code.
3) 2.1.4 debugUI
It seems that the debug UI is broken - the UI buttons do exist but are nowhere to be seen. A hot fix would be using the 'markersAreaEnabled' span style for the div
containing the buttons (see this source bit).
It's all in this glitch, you can find it under the phrase 'CHANGES HERE' in the arjs code.

Iterate over Umbraco getAllTagsInGroup result

I'm trying to get a list of tags from a particular tag group in Umbraco (v4.0.2.1) using the following code:
var tags = umbraco.editorControls.tags.library.getAllTagsInGroup("document downloads");
What I want to do is just output a list of those tags. However, if I output the variable 'tags' it just outputs a list of all tags in a string. I want to split each tag onto a new line.
When I check the datatype of the 'tags' variable:
string tagType = tags.GetType().ToString();
...it outputs MS.Internal.Xml.XPath.XPathSelectionIterator.
So question is, how do I get the individual tags out of the 'tags' variable? How do I work with a variable of this data type? I can find examples of how to do it by loading an actual XML file, but I don't have an actual XML file - just the 'tags' variable to work with.
Thanks very much for any help!
EDIT1: I guess what I'm asking is, how do I loop through the nodes returned by an XPathSelectionIterator data type?
EDIT2: I've found this code, which almost does what I need:
XPathDocument document = new XPathDocument("file.xml");
XPathNavigator navigator = document.CreateNavigator();
XPathNodeIterator nodes = navigator.Select("/tags/tag");
nodes.MoveNext();
XPathNavigator nodesNavigator = nodes.Current;
XPathNodeIterator nodesText = nodesNavigator.SelectDescendants(XPathNodeType.Text, false);
while (nodesText.MoveNext())
debugString += nodesText.Current.Value.ToString();
...but it expects the URL of an actual XML file to load into the first line. My XML file is essentially the 'tags' variable, not an actual XML file. So when I replace:
XPathDocument document = new XPathDocument("file.xml");
...with:
XPathDocument document = new XPathDocument(tags);
...it just errors.
Since it is an Iterator, I would suggest you iterate it. ;-)
var tags = umbraco.editorControls.tags.library.getAllTagsInGroup("document downloads");
foreach (XPathNavigator tag in tags) {
// handle current tag
}
I think this does the trick a little better.
The problem is that getAllTagsInGroup returns the container for all tags, you need to get its children.
foreach( var tag in umbraco.editorControls.tags.library.getAllTagsInGroup("category").Current.Select("/tags/tag") )
{
/// Your Code
}

Pulling Images from rss/atom feeds using magpie rss

Im using php and magpie and would like a general way of detecting images in feed item. I know some websites place images within the enclosure tag, others like this images[rss] and some simply add it to description. Is there any one with a general function for detecting if rss item has image and extracting image url after its been parsed by magpie?
i think reqular expressions would be needed to extract from description but im a noob at those. Please help if you can.
I spent ages searching for a way of displaying images in RSS via Magpie myself, and in the end I had to examine the code to figure out how to get it to work.
Like you say, the reason Magpie doesn't pick up images in the element is because they are specified using the 'enclosure' tag, which is an empty tag where the information is in the attributes, e.g.
<enclosure url="http://www.mysite.com/myphoto.jpg" length="14478" type="image/jpeg" />
As a hack to get it to work quickly for me I added the following lines of code into rss_parse.inc:
function feed_start_element($p, $element, &$attrs) {
...
if ( $el == 'channel' )
{
$this->inchannel = true;
}
...
// START EDIT - add this elseif condition to the if ($el=xxx) statement.
// Checks if element is enclosure tag, and if so store the attribute values
elseif ($el == 'enclosure' ) {
if ( isset($attrs['url']) ) {
$this->current_item['enclosure_url'] = $attrs['url'];
$this->current_item['enclosure_type'] = $attrs['type'];
$this->current_item['enclosure_length'] = $attrs['length'];
}
}
// END EDIT
...
}
The url to the image is in $myRSSitem['enclosure_url'] and the size is in $myRSSitem['enclosure_length'].
Note that enclosure tags can refer to many types of media, so first check if the type is actually an image by checking $myRSSitem['enclosure_type'].
Maybe someone else has a better suggestion and I'm sure this could be done more elegantly to pick up attributes from other empty tags, but I needed a v quick fix (deadline pressures) but I hope this might help someone else in difficulty!

Image tag not closing with HTMLAgilityPack

Using the HTMLAgilityPack to write out a new image node, it seems to remove the closing tag of an image, e.g. should be but when you check outer html, has .
string strIMG = "<img src='" + imgPath + "' height='" + pubImg.Height + "px' width='" + pubImg.Width + "px' />";
HtmlNode newNode = HtmlNode.Create(strIMG);
This breaks xhtml.
Telling it to output XML as Micky suggests works, but if you have other reasons not to want XML, try this:
doc.OptionWriteEmptyNodes = true;
Edit 1:Here is how to fix an HTML Agilty Pack document to correctly display image (img) tags:
if (HtmlNode.ElementsFlags.ContainsKey("img"))
{ HtmlNode.ElementsFlags["img"] = HtmlElementFlag.Closed;}
else
{ HtmlNode.ElementsFlags.Add("img", HtmlElementFlag.Closed);}
replace "img" for any other tag to fix them as well (input, select, and option come up frequently). Repeat as needed. Keep in mind that this will produce rather than , because of the HAP bug preventing the "closed" and "empty" flags from being set simultaneously.
Source: Mike Bridge
Original answer:
Having just labored over solutions to this issue, and not finding any sufficient answers (doctype set properly, using Output as XML, Check Syntax, AutoCloseOnEnd, and Write Empty Node options), I was able to solve this with a dirty hack.
This will certainly not solve the issue outright for everyone, but for anyone returning their generated html/xml as a string (EG via a web service), the simple solution is to use fake tags that the agility pack doesn't know to break.
Once you have finished doing everything you need to do on your document, call the following method once for each tag giving you a headache (notable examples being option, input, and img). Immediately after, render your final string and do a simple replace for each tag prefixed with some string (in this case "Fix_", and return your string.
This is only marginally better in my opinion than the regex solution proposed in another question I cannot locate at the moment (something along the lines of )
private void fixHAPUnclosedTags(ref HtmlDocument doc, string tagName, bool hasInnerText = false)
{
HtmlNode tagReplacement = null;
foreach(var tag in doc.DocumentNode.SelectNodes("//"+tagName))
{
tagReplacement = HtmlTextNode.CreateNode("<fix_"+tagName+"></fix_"+tagName+">");
foreach(var attr in tag.Attributes)
{
tagReplacement.SetAttributeValue(attr.Name, attr.Value);
}
if(hasInnerText)//for option tags and other non-empty nodes, the next (text) node will be its inner HTML
{
tagReplacement.InnerHtml = tag.InnerHtml + tag.NextSibling.InnerHtml;
tag.NextSibling.Remove();
}
tag.ParentNode.ReplaceChild(tagReplacement, tag);
}
}
As a note, if I were a betting man I would guess that MikeBridge's answer above inadvertently identifies the source of this bug in the pack - something is causing the closed and empty flags to be mutually exclusive
Additionally, after a bit more digging, I don't appear to be the only one who has taken this approach:
HtmlAgilityPack Drops Option End Tags
Furthermore, in cases where you ONLY need non-empty elements, there is a very simple fix listed in that same question, as well as the HAP codeplex discussion here: This essentially sets the empty flag option listed in Mike Bridge's answer above permanently everywhere.
There is an option to turn on XML output that makes this issue go away.
var htmlDoc = new HtmlDocument();
htmlDoc.OptionOutputAsXml = true;
htmlDoc.LoadHtml(rawHtml);
This seems to be a bug with HtmlAgilityPack. There are many ways to reproduce this, for example:
Debug.WriteLine(HtmlNode.CreateNode("<img id=\"bla\"></img>").OuterHtml);
Outputs malformed HTML. Using the suggested fixes in the other answers does nothing.
HtmlDocument doc = new HtmlDocument();
doc.OptionOutputAsXml = true;
HtmlNode node = doc.CreateElement("x");
node.InnerHtml = "<img id=\"bla\"></img>";
doc.DocumentNode.AppendChild(node);
Debug.WriteLine(doc.DocumentNode.OuterHtml);
Produces malformed XML / XHTML like <x><img id="bla"></x>
I have created a issue in CodePlex for this.

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