I've also considered the metadata interfaces we use, and I am not sure the current approaches are any good.
Most metadata formats are designed in a way specific to that format, eg. some have arbitrary levels of nesting, others have a flat structure, etc. But most are designed to be stored in any image format. So instead of a Imaging.getMetadata() method that tries to unify all metadata into one common interface - and does so badly, because eg. EXIF can have nested subdirectories and this information is lost - maybe we should have: Imaging.getExifMetadata() Imaging.getIptcMetadata() Imaging.getXmpMetadata() Regards Damjan On Tue, Jul 3, 2012 at 9:19 PM, Farrukh Najmi <farr...@wellfleetsoftware.com> wrote: > > Updated proposed patch with following new changes: > > Add getValue() method to nested class IImageMetadataItem. These return the > value of the item as an Object allowing for values of various types to be > returned. > > > On 07/03/2012 11:01 AM, Farrukh Najmi wrote: > > Moving this thread to dev list as it seems to be more appropriate there.... > > Attached is a patch to the IImageMetadata.java that reflects my revised > proposal thinking this through in conjunction with the proposed solution in > another thread... > > Add a getMetadataSpecification() method to IImageMetadata so we can manage > the metadata specification that defines the metadata > Add getMetadata() to nested class IImageMetadataItem to get back at the > parent IImageMetadata instance so we can access the metadata specification > information managed from an IImageMetadata instance > Add getId(), getName(), getDescription() methods to nested class > IImageMetadataItem. These are the key triplet of info about the metadata > item that is needed in my experience > > Of course implementations of these two interfaces would need to also be > updated to support the new methods according to proposed semantics. I would > be happy to contribute in any way that I can and as requested. > > Dev team colleagues, please weigh in on the proposal. Thanks for your > awesome work to create this project and for considering this proposal. > > On 07/02/2012 07:12 PM, Farrukh Najmi wrote: > > > Here is a proposed change to the API that would help my scenario... > > Modify the org.apache.commons.imaging.common.ImageMetadata$Item class to > have the following additional methods: > > getMetadataSpecification() method that returns a constant String such as > "IPTC:1.1", "EXIF:2.1", "EXIF:2.2" > getId() method that returns a unique id as follows: > > For EXIF return the Field Name as in Table 3 TIFF Rev. 6.0 Attribute > Information Used in Exif in the Exif spec. > For IPTC return the IptcRecord..iptcType.getType() > > This would allow the first code pattern below to identify each item based on > a specific metadata field defined by a specific specification. > > Thoughts? > > On 07/02/2012 06:18 PM, Farrukh Najmi wrote: > > > Hi Guys, > > I am trying to use commons-imaging latest svn bits to write a program that > will read standard metadata such as Exif and IPTC from images in a variety > of image formats using code that is as image format neutral as possible. The > goal is to store each class of metadata (e.g. Exif, IPTC, ...) in a separate > Map where the key ide > > > -- > Regards, > Farrukh > > Web: http://www.wellfleetsoftware.com > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org > For additional commands, e-mail: dev-h...@commons.apache.org > > ntifies a metadata attribute identifier defined by the standard and a value > that is the metadata attribute's value. > > Here are two patterns I have identified for reading the metadata by looking > at test programs and code.... > > 1. Read metadata items without considering image format or metadata > standard. > > IImageMetadata metadata = Imaging.getMetadata(is, "Oregon > Scientific DS6639 - DSC_0307 - iptc added with irfanview.jpg"); > List<? extends IImageMetadata.IImageMetadataItem> items = > metadata.getItems(); > > int i=0; > for (IImageMetadata.IImageMetadataItem iitem : items) { > ImageMetadata.Item item = (ImageMetadata.Item)iitem; > System.err.println("Index: " + i + " Key: " + > item.getKeyword() + " Value: " + item.getText() + " class: " + > iitem.getClass()); //common.ImageMetadata$Item, Tiff.TiffImageMetadata > i++; > } > > > This is closest to what I want. The EXIF metadata is represented by > org.apache.commons.imaging.formats.tiff.TiffImageMetadata$Item and I can get > at the TiffField and its tagName and value (good). However, IPTC metadata is > represented by org.apache.commons.imaging.common.ImageMetadata$Item. This > class seems to have no link back to the > org.apache.commons.imaging.formats.jpeg.iptc.IptcRecord and thus I cannot > find a way to get the attribute defined by the IPTC spec under the IIM > mapping rows. > > > 2. Read Exif and IPTC separately using following metadata and image format > specific patterns as shown below... > > //Read EXIF > JpegImageMetadata metadata = (JpegImageMetadata) > Imaging.getMetadata(is, "Oregon Scientific DS6639 - DSC_0307 - iptc added > with irfanview.jpg"); > TiffImageMetadata exifMetadata = metadata.getExif(); > List<TiffField> fields = exifMetadata.getAllFields(); > > int i=0; > for (TiffField field : fields) { > String key = field.getTagName(); > Object value = field.getValue(); > String fieldName = field.tagInfo.name; > System.err.println("Index: " + i + " Key: " + key + ", > Value: " + value + ", valueType: " + value.getClass()); > i++; > } > > //Read IPTC > JpegImageMetadata metadata = (JpegImageMetadata) > Imaging.getMetadata(is, "Oregon Scientific DS6639 - DSC_0307 - iptc added > with irfanview.jpg"); > JpegPhotoshopMetadata psMetadata = metadata.getPhotoshop(); > List oldRecords = psMetadata.photoshopApp13Data.getRecords(); > > for (int j = 0; j < oldRecords.size(); j++) { > IptcRecord record = (IptcRecord) oldRecords.get(j); > System.err.println("Key: " + record.iptcType.getName() + " > (0x" > + Integer.toHexString(record.iptcType.getType()) > + "), value: " + record.value); > } > > Above gives me all the linkage back to specification defined metadata fields > but is less desirable because it metadata and image format specific. > > I feel that it would be ideal to support a generic api that is agnostic to > metadata and image format but provides a reference back to the specification > defined field (attribute) identifier some how. > > I would very much appreciate some ideas from dev team on how we could > improve the api to support providing a reference back to a specification > defined field in a metadata and image format neutral manner. > > My apologies if I am missing an obvious solution while I am getting familiar > with the code. > > > > > -- > Regards, > Farrukh > > Web: http://www.wellfleetsoftware.com > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org > For additional commands, e-mail: dev-h...@commons.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org For additional commands, e-mail: dev-h...@commons.apache.org
