![]() ![]() The end of the XMP packet is basically where the next section starts. The exiftool framework above shows us a size of 28430 bytes, which is 2 bytes off, probably due to not counting the 2 bytes that represent the total size of the section. Thus we have 31 bytes at the start of the XMP section for the namespace (29 bytes) and the representation of the size itself (2 bytes). In our image the size is o\x10 (encoded as ASCII - thus 6F10 in hexadecimal format) which corresponds to 28432 bytes. The rest of the bytestring is the XMP packet itself. Then we have 2 bytes that indicate the size of the XMP packet and 29 bytes for the namespace. \xff\xe1 indicates the value of the field name APP1 which has the size of 2 bytes. According to the XMP specification the following line indicates the beginning of the XMP specification. We run the following piece of code to see how the bytestring looks like. Thus to be completly sure that no information is lost, changed or reformatted we can directly copy the whole XMP part of the bytestring to the new image. There also might be some custom XMP data that are not be copied. > exiftool -v new.jpgĪs you see there is discrepancy of around 9000 bytes, caused by a different XMPToolkit Tag and some reformatting of the bytestring. Let's check with exiftool just to be sure that it is not the fault of ImageMagic not reading meta data correctly. Let us now check the size of the XMP section in the image we just created. Metadata_1 = pyexiv2.ImageMetadata('original.jpg') The other method involves using the p圓exiv2 library: import pyexiv2 Xmpfile2 = XMPFiles(file_path = dest, open_forupdate = True) Xmpfile = XMPFiles(file_path = source, open_forupdate = True) ![]() With the Python XMP Toolkit we can copy the data the following way. The destination image that will receive the XMP content will be created on the fly. Let us look more closely at this using ImageMagick to check the size: > identify -verbose original.jpgĪnother way to check is with the ExifTool by Phil Harvey: > exiftool -v original.jpg The main problem with those frameworks is that after copying the XMP data to another image, the size of the XMP metadata changes.įor the following experiments we will use this test image, which we will refer as original.jpg. Pythom XMP Toolkit thats works with XMP image data.p圓exiv2, which is a Python binding to Exiv2 which is a tool for managing image data, and. ![]() There exist generally two ways to copy XMP data in Python using a dedicated framekwork. It turns out that this isn't that straightforward when dealing with XMP metadata. Sometimes it is necessary that we alter an image (resize or change pixels), but want to keep all the metadata. XMP (Extensible Metadata Platform) is a metadata format introduced by Adobe Systems Inc. Read how it's done correctly.Ģ7 October 2021, by Cezary Zaboklicki Ask a question Introduction Copying XMP metadata between images isn't straightforward. ![]()
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