Archive for category High Definition
Network Rendering with MetaFuze
Posted by Dylan in Avid, High Definition, RED, Video/TV on February 4th, 2010
Avid MetaFuze is a tool from Avid Technology that converts various video formats (most notably DPX and RED RAW) into native DNxHD media that can be used with Avid’s editing products. The product ships with two interfaces – a GUI for direct transcoding, and a command-line version more suitable for scripting.
A small number of modestly powered computers can be put to work transcoding media from a large pool in a shorter time. However this isn’t something that MetaFuze will handle natively and must be managed.
Networking
The most important part of distributing the transcoding over a number of network computers is making sure all the client computers have access to the source files.
To achieve this, the easiest thing is to create a network share on the ‘Master’ computer which contains all the source files for transcoding. Once the share is created, you can then map this to the same drive letter on all computers, which will ensure that file paths are consistent on all client computers.
In this case, we’ll assume that your local desktop PC (called ‘WORKER’) contains all the source files in E:\Video\REDMedia – create a network share for the E:\Video folder, which will then be accessible as \\WORKER\Video on the local network. On all computers (including your own desktop) you can then map that network location to the drive letter Z:
Job Setup
MetaFuze doesn’t natively provide any method for distributing job instructions to multiple machines. All transcode jobs are stored in a single file. To address this I’ve created a tool called BatchFuze Extactor which will take the XML project file from MetaFuze and split it into single files for each source file.
To create these job files simply follow the standard procedure for creating a transcode batch in MetaFuze, save the project, then open that project XML in BatchFuze Extractor and choose where to save the output files.
For the purposes of networking it is important that all file paths be accessible to all client computers, so even if the source files reside on a local drive on the computer that is running MetaFuze it is important that the source files be accessed with a network path. Following the basic sharing method above this would mean it’s important to location the files through the Z: drive.
If the files are to be rendered back to a network drive, it’s equally imporant that the target location for transcoded files also be available on all client computers. If you’re planning to render to the local client machines then the path must be valid on all client computers (create E:\Video\Transcoded on all rendering computers, for example).
Whatever file locations are shown in MetaFuze when you create the Transcode batch are the ones that will be referred to by the client computer when transcoding.
Distributing The Work
Once you have a collection of individual XML batch files you could simply roughly divide them on to the client computers, and get MetaFuze to process each batch in turn. This will require a simple batch file.
Alternatively I am currently developing an application to manage this process across a network. One computer operates a server, distributing the batch jobs, and the remaining computers run a client which communicates with the server, receives jobs and passes those jobs on to MetaFuze for processing.
This application is currently at a Beta stage, if you’re interested in testing it, please get in touch with me by email: batchfuze -AT- dylanreeve.com
Downconversion in Media Composer
Posted by Dylan in Avid, High Definition, Video/TV on December 6th, 2009
In a recent thread on the Avid Community Forums there was some discussion of the quality of Avid’s downconversion from HD to SD. I have used various downconvert methods from within Media Composer in the past and have never had any serious problems with any of the results, but I figured I might be able to conduct some vaguely reasonable tests. Read the rest of this entry »
Video Salad
Posted by Dylan in High Definition, Video/TV on June 26th, 2009
In days gone by there was two types of video – PAL and NTSC. That was it. There were different tapes, but the video that came out was basically all the same. Any machine with the right plugs could plug into any other. Read the rest of this entry »
XDCAM EX Workflow in Avid
Posted by Dylan in Avid, High Definition, Video/TV on February 23rd, 2009
NOTE: Since this article was written Avid has introduced AMA into Media Composer (from version 3.5) which greatly simplifies the workflow with EX material. From Media Composer 3.5 onward working with XDCAM (SD, HD and EX) and P2 in Avid is incredibly simple and immediate.
I’m a fan of XDCAM EX. I like the format and think it offers great quality given it’s bitrate and cost. The cameras are good the SxS media is pretty decent. I have my general reservations and concerns about Solid-State recording, but assuming you have a reasonable process for managing backups you should be fine.
When EX first came out there was no EX support. It was added in Media Composer 3.0.5 I believe. Shortly after that happened Sony released version 2 of their Clip Browser software which had a ‘Avid AAF’ export function that made it a lot easier to get EX footage into Media Composer. Avid even posted a tutorial about the process.
Essentially this feature unwraps the MP4 XDCAM EX files and re-wraps them as MXF Op-Atom (Avid’s mediafile container) and places those files directly into one of Avid’s media directories (such as F:\Avid MediaFiles\MXF\2) and then creates an AAF file that contains a clip describing that shot (basically the easiest way to get the shots into a bin). This process is simple and reasonably quick and works fine… Or so I thought.
What is lacking in this process in Metadata control. When Clip Browser generates the MXF files it’s creating files that lack some of the metadata that Avid would normally use to relink a clip to media. Most obviously there is no Source or Disc Label associated with any of these clips. What this means is that Avid cannot relink this media. So if the Avid MXF file you create from Clip Browser is lost at all it cannot be relinked. Even going back to Clip Browser and re-exporting the same clip or clips to the same media directory will not create media that Avid will reassociate with existing clips or sequences.
Basically if you import clips this way you are absolutely locked in to those specific media files. No backup short of storing the actual files as they are created in the Avid MediaFiles directory will allow a recovery or relink.
The easiest way to avoid this problem is actually to use the older process. Using Clip Browsers ‘MXF for NLE’ export setting. This will create OP-1A MXF files that you can then import into Media Composer (the Avid will rewrap them as OP-Atom and relocate them to it’s media directory). It is a slower process, but as it’s a standard import process all the necessary Metadata will be stored with the clips to allow a Batch Import later.
Ideally this will soon not be necessary if Avid incorporates EX import directly into Media Composer, cutting out the Clip Browser middle-man.
RED Expectations
Posted by Dylan in High Definition, RED on July 30th, 2008
The following is the text of a post I made on a forum as a general response after someone was asking about how best to set up budget/low-end 2K monitoring and finishing for the FCP system..
I reckon Jim Jannard and RED have a lot to answer for when it comes to messing up expectations.
I love the RED One camera, I have now worked on set and in post on a number of RED shoots (all destined for no greater than 1080 in the end). It’s a camera for $18,000 (we’ll ignore lenses and accessories) that can shoot 4K!
Every indie filmmaker in the country is now convinced they can cut their opus in 4K in FCP and have it projected at the local Multiplex for less than it costs to sponsor a kid in Africa.
They are very mistaken. Yes, they can shoot RED, in 2K, 3K or even 4K. Yes they can cut it in FCP (or Avid, or Premiere, or whatever if they are game to play around). But the 2K or 4K finish, there’s the rub. FCP can, in theory, work with 2K resolutions. But it’s far from simple at that point, it’s not like video. You can’t just spit it out. There are huge issues to consider about LUTs, delivery, compression, audio mastering.
My advice to anyone thinking they ought to get into 2K on the cheap is, don’t. Wait. Stop. Think about it. FCP and Color and all the rest are good tools, but this isn’t really their strongest area, and chances are it’s not yours either. There are product and people who really know what they are doing and do it well. Those people and products are what you need. Shoot 4K, edit the proxies in FCP or Avid or whatever, but when it comes to the finishing, if you want any bigger than 1080 then it’s time to find a friendly expert. Hire/beg some time on a Scratch or Pablo or Smoke with someone who really knows their stuff. The future nightmares will be reduced and the quality of the end product will be increased.
2K will come to your desktop in time, but wait a while.