Sunday, February 28, 2010

Ending with a bang

Well April seems to be THE month for Tower 37. April 2009 was our premiere month and we showed in 7 different fests. This April, we are already slated for 9 fests and there are still some we haven't heard back from. I keep the calendar as up to date as possible, so use it.

Some March/April festivals of note:
I have one story to share in advance of the big fest month; others will certainly follow.

You go to a film festival and want to see some animation, right? So you go to the animated shorts block. Makes sense. Unfortunately, though, at the Tiburon International Film Festival this week Tower 37 is NOT in the animated shorts block. Which wouldn't itself be a tragedy because we're paired with what looks like a cool movie about surfing. Except... they're at the exact same time. So you have to choose: animated shorts or Tower 37. I hope there's a good surfing contingent in Tiburon.

Friday, February 26, 2010

Making a DCP entirely with open source tools

this technique is now obsolete - try the latest method instead!

Here are the steps I followed to produce a DCP for the 11-minute short film The Incident at Tower 37. It has ingested and played properly on a Doremi DCP-2000. The projector was a Barco model. Everything below was done on a Linux machine.

Credit where it is due: as I mentioned in an earlier post, I'm building off the work of the people behind asdcplib and OpenCinemaTools, and the users on the Red user forums who have published software and instructions that they have used/created while traversing this bumpy path. Big thanks to Wolfgang, Pavel, Marc, Samson, and Josiah.

In the interest of brevity, I'm not going to explain why I chose program X over program Y -- those interested can read my previous posts where I go into more of those details. Also, I'm not trying to present the be-all, end-all DCP manual here; this is just what worked for me!

Step 0: prepare sources

My source video was a 24fps lossless QuickTime movie, 1920 x 1080 (16:9). For the purposes of this document, call it

My source audio comprised of six wav files for Dolby 5.1 surround, each 48kHz mono.

Step 1: export PNGs from source QuickTime movie

Tool: ffmpeg
Version: SVN-r21770 (compiled locally)

ffmpeg -r 24 -i -f image2 %08d.png
This marches through the video file outputting a lossless, compressed PNG 24 times per second.

Step 2: convert to 12 bit per channel XYZ color images
Tool: ImageMagick's convert
Version: 6.5.9 (compiled locally)
Must be run once per PNG frame.

convert FRAME.png -type TrueColor -alpha Off \
-background black -extent 2048x1080-64 -depth 12 \
-gamma 0.454545 \
-recolor "0.4124564 0.3575761 0.18
04375 \
0.2126729 0.7151522 0.0721750 \
0.0193339 0.1191920 0.9503041" \
-gamma 2.6 FRAME.tif
This takes a 1920 x 1080 PNG from step 1, removes any alpha, pads the image with 64 pixels of black on each side so that it becomes 2048 x 1080, sets the bit depth to 12 bits per pixel, and does a linear-space color shift from RGB->XYZ. Then it writes the image out as a TIFF.

Upon further reading, I interrogated my own decision to force the 1920 x 1080 images into a 2048 x 1080 container by padding with black. Apparently, you only need one dimension of the source imagery to match either 2048 or 1080 and the OpenJPEG encoder will do the right thing.

The new conversion line I used today omits the padding and looked stellar at the theater just moments ago:
convert FRAME.png -type TrueColor -alpha Off -depth 12 \
-gamma 0.454545 \
-recolor "0.4124564 0.3575761 0.18
04375 \
0.2126729 0.7151522 0.0721750 \
0.0193339 0.1191920 0.9503041" \
-gamma 2.6 FRAME.tif
This must be run one frame at a time, but it's very easy to distribute ranges of frames to multiple processors if you have them.

Step 3: convert TIFFs to JPEG-2000
Tool: OpenJPEG's image_to_j2k
Version: locally from subversion revision 543)
Must be run once per TIFF frame.
image_to_j2k -cinema2K 24 -i FRAME.tif -o FRAME.j2c
This takes longer per frame than convert, in my experience. About 2x longer. Also easy to distribute to many machines, however.

Step 4: make all the necessary DCP files
Tools: OpenCinemaTools
Version: 1.1.2 (compiled locally)

This step has five substeps, each of which generates one or more of the files needed for the DCP. Naming conventions are very important in DCP land, so I highly recommend that you read about them yourself and make informed choices. When you see DCPFULLNAME below, that's shorthand for what I used, which was the mouthful:
Command A (create a video MXF file from the folder of J2K files):
asdcptest -v -L -c FOLDER_OF_J2KS
Command B (create an audio MXF file from the six wavs):
asdcptest -v -L -c left.wav right.wav \
center.wav sub.wav surrLeft.wav surrRight.wav
Command C (create an XML composition playlist):
mkcpl --kind feature --title DCPFULLNAME \
--annotation DCPFULLNAME --norating \ > PROJ.cpl.xml
Do check the output of command C and confirm that the durations of both video and audio are identical. The XML tag for this is "IntrinsicDuration."
Command D (create an XML packing list):

mkpkl --issuer BitFilms --annotation DCPFULLNAME \ PROJ.cpl.xml > PROJ.pkl.xml
Command E (create the ASSETMAP and VOLINDEX XML files):
mkmap --issuer BitFilms \ PROJ.cpl.xml PROJ.pkl.xml

I used a bit of shorthand above since I did not identify enclosing folders. I suggest that if you make a DCP this way, you use temporary folders for all the inputs (and the results of steps 1-3), then create a finalDCP folder which you populate with only the files that will be part of the eventual DCP itself (namely, the 2 mxfs and the 4 XML files that come from step 4).

Step 5: Get the DCP onto a Hard Drive
Tools: regular linux shell

I need to get the specific instructions from Josiah, but basically we formatted a UDF disk solely for the purpose of holding the DCP (partition type 0x83 if I remember correctly). Then I copied over the 6 files that emerged from step 4 right to the root of the new disk. And it's done!

Some quick notes:
  • It is important that you check your XML files to make sure the file paths don't contain any incorrect information: if you aren't careful during step 4, your file paths in the XML may be incorrect! Here's what one of my entries looks like in my final ASSETMAP.xml file as an example: file:///
  • I don't know what happens if your audio and video durations are different, so I was careful to make sure mine were not. Check them in the CPL (the tag is ).
  • Work with a small movie file for starters, a minute or less, until you get the steps ironed out. Then move to your full film.
I hope this is useful for some of you! If you see any mistakes above, or have suggestions to improve or generalize this pipeline, please let me know.

Monday, February 8, 2010

Making a DCP, post 4

Today I got to watch my latest DCP of The Incident at Tower 37 in its entirety at the theater! 5.1 surround! Crisp and clear picture! The only problem is, it looked like this:

instead of like this:

You just can't have a movie about water where all the water is orange/brown.

So what the heck went wrong?

My current image transformation pipeline is as follows:

QuickTime movie -> PNG files (by way of mplayer)
PNG files -> 12 bit per pixel, color corrected TIFF files (by way of Imagemagick's convert)
TIFF files -> JPEG-2000 files (by way of image_to_j2k, courtesy of openjpeg)

Step one of figuring out this problem: isolate the place where it appears. Luckily, my test from last week looked great, so I have an example of a working set of images to compare with the broken set. As it turns out, my original PNG files are messed up. I can't believe it. I generated over 15,000 PNG files and never actually looked at one of them to confirm that they were right. Rookie move.

The good news? The rest of the pipeline worked great 'cause my bad-looking PNGs (with the brown water) made it all the way into bad-looking JPEG-2000s on the theater screen. Half full, baby!

So let's dig into the PNG making process. It hasn't changed since I made the working test. In other words, my mplayer line is the exact same as the mplayer line I used for the test. So the problem is likely further upstream.

What did change? The source material. The excerpt I tested on last week was a QuickTime movie I made by trimming a final version of the film using QuickTime Pro on a Mac. I trimmed it, then saved it out, flat. Aha. This could be the problem. The QuickTime file I used for the full version had a number of video tracks on it (since I added color bars within QT Pro). Perhaps mplayer didn't know which stream to use, or it somehow misinterpreted the stream itself?

Oh now I have fallen into the rabbit hole. I get different results from mplayer's PNG exporter based on what frame I start with, on what kind of PNG compression I set, and more! It appears to be completely unreliable, at least with my multi-layered QuickTime source file. I'm going to take a suggestion I was given online and check out ffmpeg as an option to create the PNGs, and I'm also going to be cleaner from the outset and make a flat QT source movie with only one video channel.

More to come. Having to export and re-convert all these images again is going to force me to finally distribute this process to our cluster. I can't stand having days pass between tests!

Tuesday, February 2, 2010

Making a DCP, post 3

Victory! The smallest taste, but a good one.

After last week's close-but-no-cigar attempt, I realized I missed a critical last step in my DCP-making script. I had somehow spaced on creating the ASSETMAP and VOLINDEX XML files. Once I caught this, I rolled out a new DCP and brought it to the theater today. Plugged it in, and was pleased that the ingest feature recognized my disk. Instead of the properly-formatted DCP name, however, I saw a UUID in the ingest window. So there are still some kinks to work out.

Aside for the geeky: the UUID that appeared in the ingest window was the UUID of the packing list. I think there's an XML annotation tag or something similar I could have used in that pkl that would have made a better name appear in the ingest window.

Once we ingested the DCP, the next problem was that the CineLister elements window which lists all the DCPs didn't show ours. A reboot made it appear (my theory was that relaunching the program would re-scan the assets folder -- never got to test that theory but the reboot worked).

Aside: the list was sorted by the ContentKind tag, as in, feature, trailer, test, and so on. This is set in the Composition Playlist (CPL) file like so: test.

At this point my pulse quickened. Dave helped build a new playlist with the proper magic incantations to first show black then configure the projector to 2K flat, and we ran it. Though there were scaling issues (he said the projector was at 1k instead of 2k and that it was an easy fix), there was Leed, big as hell, climbing up the side of the tower from u2_01. That's the same shot that opens the online teaser. Heck, I'll embed it again. Too many posts without color recently.

A word on color: the color looked beautiful. I need a longer exposure to it before I say for sure, but thanks to Pavel and Wolfgang for the color transformation matrix they shared on the RedUser forum about DCPs. So far, it's worked great.

So this week I'm going to try and roll out a complete DCP, with 5.1 audio. I'll see if I can work out the kinks in the naming issues, but with luck I'll have more to report next week from the theater!