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| *One line summary* | Validating JPEG2000 files after conversion from TIFF and tracing source of errors \\
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| *Detailed description* | The workflow consists of the following: \\
1 Create images as RAW files \\
2 Convert to TIFF in Lightroom \\
3 Convert to JPEG2000 using LuraWave \\
4 Open each JPEG2000 in Photshop CS4 to validate it can be opened (scripted) \\
5 Check for error logs \\
6 On the all clear, RAWs and TIFFs are deleted. \\
7 JPEG2000s are preserved. \\
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Possible issues arising from migration of the content: \\
* Resulting images are not saved or are truncated due to the migration or write to disk stopping prematurely
* Image metadata/header information is lost
* Resulting pixel data does not match the source
* Colour space information is lost
* Resulting JPEG2000 is not renderable
* Resulting JP2 does not match the intended profile \\
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Regarding validity of the JP2's, we used JHOVE to validate files when we were testing LuraWave, but we do not use it as part of the workflow. When the files are loaded into the DAM, JHOVE will be used internally in the DAM to characterise the files, and to therefore extract administrative metadata for long-term management/migration purposes. The files are then backed up to a WORM storage system. \\
Regarding validity of the JP2's, we used JHOVE to valide files when we were testing LuraWave, but we do not use it as part of the workflow. When the files are loaded into the DAM, JHOVE will be used internally in the DAM to characterise the files, and to therefore extract administrative metadata for long-term management/migration purposes. The files are then backed up to a WORM storage system. \\
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Ideally, we would be able to validate the JP2's _before_ ingest to the DAM, so we can detect and rectify errors before ingest and WORM'ing. Not only that the file is valid and the correct JP2 profile, but that there has been no loss of quality beyond the acceptable level determined when setting the compression level for lossy conversion. \\ |
| *Issue champion* | Christy Henshaw \\ |
| *Possible approaches* | Using JHOVE earlier in the process to validate the file validity. JHOVE is not user friendly. Unsure how this might be implemented. Perhaps it can be scripted using our soon-to-be installed workflow system, which can "call" third party systems/utilities. \\
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| *Context* | |
| *AQuA Solutions* | [AQuA:Validating TIFF to JPEG2000 migration]\\ |
| *Collections* | [Wellcome Library Digitisation |AQuA:Wellcome Library digitisation]\\ |