If a DCP (encrypted) loads fine in DOM player then does that mean its integrity is intact?
I received a DCP and upon opening it asks for the KDM. I don't have the KDM to play it at the moment but would DOM player complain if the files were not in order or if something was missing? If not then what other way exists of checking the integrity of a DCP?
Please guide.
DOM Player and DCP Integrity
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Carsten
- Posts: 2804
- Joined: Tue Apr 15, 2014 9:11 pm
- Location: Germany
Re: DOM Player and DCP Integrity
DCP-o-matic player 2.13x offers an explicit integrity check. It is not a full formal test (as e.g. dcp_inspect), but it can e.g. check for completeness of transmission and corrupt files. Yes, it can also check encrypted DCPs for integrity if you don't have a KDM.Maybe Carl will add more checks sometime.
- Carsten
- Carsten
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rickssatellite
- Posts: 3
- Joined: Thu Jun 20, 2019 10:32 pm
Re: DOM Player and DCP Integrity
Hi,
I need to run a DCP Integrity Test. I download Master DCP's and then do duplications and ship them to theaters.
When the supplier was shipping me master DCP's, I felt good about just putting them in a duplication machine and making my duplications and shipping them out. But now that they don't ship them to me anymore and I have to download them, I feel the need to run a DCP Integrity Test to make sure that my Master DCP is good, before putting them in a duplication machine and doing 20 duplications and shipping them out.
Can I do this DCP Integrity Test with DCP-o-matic?
I found a site called filmprint.cz that has a Free online DCP Integrity Test page, but JAVA requires an extensive setup, as it wants to block the various sites that are being used to run the test. I got it to work at first, but only when using Internet Explorer browser and never could get it to work at all using a Chrome browser. Recently, I cannot get it to work any more, as the test will not start and I also wondered if the site is actually taking the content, so not sure just how safe it actually is. The link for the DCP Integrity Test is http://www.filmprint.cz/online_dcp_checker.php. If this is not acceptable to post this link, I am sorry. Mod please remove or notify me and I will remove it asap.
Thank you in advance for any help.
Rick
I need to run a DCP Integrity Test. I download Master DCP's and then do duplications and ship them to theaters.
When the supplier was shipping me master DCP's, I felt good about just putting them in a duplication machine and making my duplications and shipping them out. But now that they don't ship them to me anymore and I have to download them, I feel the need to run a DCP Integrity Test to make sure that my Master DCP is good, before putting them in a duplication machine and doing 20 duplications and shipping them out.
Can I do this DCP Integrity Test with DCP-o-matic?
I found a site called filmprint.cz that has a Free online DCP Integrity Test page, but JAVA requires an extensive setup, as it wants to block the various sites that are being used to run the test. I got it to work at first, but only when using Internet Explorer browser and never could get it to work at all using a Chrome browser. Recently, I cannot get it to work any more, as the test will not start and I also wondered if the site is actually taking the content, so not sure just how safe it actually is. The link for the DCP Integrity Test is http://www.filmprint.cz/online_dcp_checker.php. If this is not acceptable to post this link, I am sorry. Mod please remove or notify me and I will remove it asap.
Thank you in advance for any help.
Rick
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Guddu
- Posts: 133
- Joined: Wed Oct 04, 2017 4:49 am
Re: DOM Player and DCP Integrity
I have been using ClairMeta for this purpose. It's really simple to setup and quite useful. Not even sure if I am allowed to talk about a third party tool here but useful nevertheless. If you need any help then feel free to write back.
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Carsten
- Posts: 2804
- Joined: Tue Apr 15, 2014 9:11 pm
- Location: Germany
Re: DOM Player and DCP Integrity
DCP-o-matic player offers a 'simple' data integrity test. It checks file hashes. That is usually sufficient if you want to test for file transfer integrity. It will take a while though, so if you do this often, you should use a very fast CPU and check from SSD. Clairmeta and dcp_inspect test many formal aspects of DCPs as well. They are maybe more advisable if you create DCPs on your own or if you assume that a DCP you received has questionable formal parameters. I never felt the need to perform such formal tests on DCPs created by DCP-o-matic. It may be useful from time to time to test new features added to DCP-o-matic (e.g. CCAPs, CPL metadata, etc.)
Keep in mind, for transmission integrity checks, a tool needs to read through the whole DCP incl. asset files (MXF). These are huge, so, doing that 'online' means that the full DCP would need to be streamed to the remote server. That doesn't make much sense.
It may be, of course, that all they offer is a JAVA/JAVASCRIPT application that does the actual test locally on your machine.
- Carsten
Keep in mind, for transmission integrity checks, a tool needs to read through the whole DCP incl. asset files (MXF). These are huge, so, doing that 'online' means that the full DCP would need to be streamed to the remote server. That doesn't make much sense.
It may be, of course, that all they offer is a JAVA/JAVASCRIPT application that does the actual test locally on your machine.
- Carsten
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rickssatellite
- Posts: 3
- Joined: Thu Jun 20, 2019 10:32 pm
Re: DOM Player and DCP Integrity
Hi,
Thank you both for your kind replies.
I download the master DCP files and they are QC'ed before I download them and then make duplications and send to 30 to 50 theaters and the time line is short. So if a venue gets one that their sever says has errors, sometimes there is not much time to send them another DCP and the shipping costs for next day are so expensive and then the venue wants me to pay for the shipping, while I am only making a small fee for providing the duplication service for the local production company.
One time we did a download that ended up having errors and had all locations having issues and had to download again and ship more DCP's out and also send out Blu-Rays in several, all to avoid the shows having to be canceled, which really gets people upset. Not only at the management of the venues, but the patrons arriving to watch the show, just to find out it was canceled.
That is when I decided I had to try and find someway to run something like the same type of integrity test that a server at the actual venue runs when they are ingesting the content. The Filmprint.cz site was fine for this, but yes, it would take a long time, depending on the size of the file which would average around 200GB and would normally take around 2 to 3 hours. But once it was complete, then I felt much better about using it as my Master and doing the duplications. It hae been working good enough that the US production company now has me do a test download from their own Filemail downloading system for the venues that can actually download them self and then I would run a test on the content I downloaded from their system and tell them it checked good and they could distribute it to all of the download sites.
I will check into both options that you both have so kindly offered to me, as for what ever reason, I still cannot get the filmprint program to work any more. I wiped out all of the Java security settings and tried setting it up again and it just is not working as before.
I also wondered about doing it online and with not knowing much about filmprint site, if that site was actually capturing the complete file and then they could do what they want with it. I am sure the owner of the content would not be to pleased to find their content on torrent sights available for download. I was not overly concerned, as the content appeals to a certain type of audience that is most likely not into downloading content that way and they actually really enjoy going to the theater to enjoy the Big Screen Experience, but still always wondered.
I also thought about trying to go to a local movie theater and ask them if I could get them to run the check, but I know that would be inconvenient to them as well or at minimum, they would need to charge me to do it.
Thanks again.
Rick
Thank you both for your kind replies.
I download the master DCP files and they are QC'ed before I download them and then make duplications and send to 30 to 50 theaters and the time line is short. So if a venue gets one that their sever says has errors, sometimes there is not much time to send them another DCP and the shipping costs for next day are so expensive and then the venue wants me to pay for the shipping, while I am only making a small fee for providing the duplication service for the local production company.
One time we did a download that ended up having errors and had all locations having issues and had to download again and ship more DCP's out and also send out Blu-Rays in several, all to avoid the shows having to be canceled, which really gets people upset. Not only at the management of the venues, but the patrons arriving to watch the show, just to find out it was canceled.
That is when I decided I had to try and find someway to run something like the same type of integrity test that a server at the actual venue runs when they are ingesting the content. The Filmprint.cz site was fine for this, but yes, it would take a long time, depending on the size of the file which would average around 200GB and would normally take around 2 to 3 hours. But once it was complete, then I felt much better about using it as my Master and doing the duplications. It hae been working good enough that the US production company now has me do a test download from their own Filemail downloading system for the venues that can actually download them self and then I would run a test on the content I downloaded from their system and tell them it checked good and they could distribute it to all of the download sites.
I will check into both options that you both have so kindly offered to me, as for what ever reason, I still cannot get the filmprint program to work any more. I wiped out all of the Java security settings and tried setting it up again and it just is not working as before.
I also wondered about doing it online and with not knowing much about filmprint site, if that site was actually capturing the complete file and then they could do what they want with it. I am sure the owner of the content would not be to pleased to find their content on torrent sights available for download. I was not overly concerned, as the content appeals to a certain type of audience that is most likely not into downloading content that way and they actually really enjoy going to the theater to enjoy the Big Screen Experience, but still always wondered.
I also thought about trying to go to a local movie theater and ask them if I could get them to run the check, but I know that would be inconvenient to them as well or at minimum, they would need to charge me to do it.
Thanks again.
Rick
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Carsten
- Posts: 2804
- Joined: Tue Apr 15, 2014 9:11 pm
- Location: Germany
Re: DOM Player and DCP Integrity
When doing mass duplication, you typically don't check formal DCP integrity - you assume it, and you only do a verification on the media/file level.
I guess, if I had downloaded a DCP, and wanted to forward copies on physical media, my strategy would be to perform a verification of the download, and then 'just' verify each copy on the file level. Depending on your copying methods, that may involve different tools.
The current hash verification method in DCP-o-matic player is quite time consuming. As far as I know, this is largely IO bound. I'd probably have to try comparing this between e.g. a conventional spinning disc and e.g. an M2 SSD. Also, conventional hash checking seems to be limited to singlethreaded operations, as it is inherently sequential. Other write/verify methods may have options for multithreaded operation. If your assets are segmented into multiple reels, you may perform multithreaded hash checks on every single reel, video and audio. If you do this on a very fast SSD, it will probably perform much faster. If you do this on a conventional spinning disc, it could actually perform worse than singlethreaded.
- Carsten
I guess, if I had downloaded a DCP, and wanted to forward copies on physical media, my strategy would be to perform a verification of the download, and then 'just' verify each copy on the file level. Depending on your copying methods, that may involve different tools.
The current hash verification method in DCP-o-matic player is quite time consuming. As far as I know, this is largely IO bound. I'd probably have to try comparing this between e.g. a conventional spinning disc and e.g. an M2 SSD. Also, conventional hash checking seems to be limited to singlethreaded operations, as it is inherently sequential. Other write/verify methods may have options for multithreaded operation. If your assets are segmented into multiple reels, you may perform multithreaded hash checks on every single reel, video and audio. If you do this on a very fast SSD, it will probably perform much faster. If you do this on a conventional spinning disc, it could actually perform worse than singlethreaded.
- Carsten
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rickssatellite
- Posts: 3
- Joined: Thu Jun 20, 2019 10:32 pm
Re: DOM Player and DCP Integrity
Thank you Carsten,
We are running the Verify DCP now.
On the very first test ran, it gave me a report about a video file not matching an audio file. I don't remember the exact wording. So I am now running it on another DCP that had originally passed the DCP Integrity Test that I ran from filmprint when I could get that program to run and see if it passes the dcpomatic verify test.
If it does verify good, then indeed there may have been something happen during the download of the other DCP and I will have to download it again and run the verify again. If the 2nd download version checks good, then it will have saved me from making duplications of a master that had problems and save all of the shipping and returns, which would cost me more that what I am going to make on the actual duplication service.
I appreciate the help.
Rick
We are running the Verify DCP now.
On the very first test ran, it gave me a report about a video file not matching an audio file. I don't remember the exact wording. So I am now running it on another DCP that had originally passed the DCP Integrity Test that I ran from filmprint when I could get that program to run and see if it passes the dcpomatic verify test.
If it does verify good, then indeed there may have been something happen during the download of the other DCP and I will have to download it again and run the verify again. If the 2nd download version checks good, then it will have saved me from making duplications of a master that had problems and save all of the shipping and returns, which would cost me more that what I am going to make on the actual duplication service.
I appreciate the help.
Rick