More and more festivals, especially short film festivals, are requesting .mov video files in Apple ProRes for screenings, but this codec is designed for “working” and is not intended for distribution, which can be a problem for festivals, filmmakers, and distributors alike, for several reasons—not only technical, but also moral, legal, and economic.
Let’s analyze this codec from a technical standpoint. First of all, Apple ProRes is a production and editing codec, for intermediate processes, and not for distribution, created by Apple for the Final Cut workflow. Let’s look at Wikipedia:
ProRes is a line of intermediate codecs, which means they are intended for use during video editing, and not for practical end-user viewing
But if festivals are dedicated to film exhibition, how is it possible that they adopt a codec created for production, and not for exhibition? Let’s continue with Wikipedia:
ProRes 422 is a DCT based[2] intra-frame-only codec and is therefore simpler to decode than distribution oriented formats like H.264.
In other words, Apple ProRes is oriented toward creating distribution formats like H.264, so once the film is edited, it is exported in H.264 for distribution and exhibition. This means that when a festival requests this codec, we understand that it has a team equipped with Final Cut and powerful hardware capable of processing all the videos it will receive, that they import it for editing, and then export it to H.264 for viewing—that is, they have a workflow more typical of a post-production company than a film festival, with all the complications and expense that entails.
Apple ProRes is packaged in a .mov file (we are in the Mac environment), with stereo sound (since we are dealing with an intermediate format, therefore it is not designed to contain 5.1 audio), it has no subtitle support, and even if we send the subtitles on separate tracks, it doesn’t matter, because all that material is lost when importing it for editing. In other words, festivals that work with Apple ProRes forget that digital files are not only made up of video, but also audio and subtitles (which forces one to “burn” the subtitles into the image, when there are other simple options to incorporate subtitles as separate tracks).
Furthermore, it is a proprietary Apple codec, which is not free, nor open source, nor is it covered by MPEG (Moving Picture Expert Group), which is the working group responsible for establishing standards for audio and video transmission (see Wikipedia again)—that is, Apple ProRes is not, by any means, a standard codec. And there is no need to resort to this type of codec, when distribution standards exist, such as MPEG4 Part 10, H.264.
Continuing from a technical standpoint, distribution codecs are lossy codecs, which compress to achieve small file sizes, but maintain high quality. This is why H.264 has been very successful as an HD standard, maintaining good quality in small files, making it easy to transport and screen. But Apple ProRes, which is not designed for distribution, compresses much less, so a short film of about 20 minutes can take up more than 20 GB (almost like a DCP), whereas in H.264 it would take up about 3 or 4 GB, and it is certainly very difficult to screen such a heavy file from a computer, not to mention that it could only be done with an Apple computer. That is why distribution formats exist, adapted to viewing and screening needs (in the case of festivals).
Some festivals request this codec to compile festival sessions on Blu-ray discs, doing the H.264 export themselves (which doesn’t make much sense, see this post about digital files versus Blu-ray), and others compile all the videos together in H.264 for sessions and screen from the computer, which also doesn’t make much sense, when all media players can create playlists and screen all the videos in the order we want, simply by requesting H.264 directly from producers and distributors—easy and simple. In some cases, all the short films are exported together again in Apple ProRes for screening, but in this case we would have to play an excessively heavy file that would require a very powerful computer and would be very difficult to play.
In summary, if from a technical standpoint festivals have to export to H.264 for viewing digital files, why don’t they request H.264 directly? The most common answer I have encountered is quality, since Apple ProRes has higher quality than H.264, and it is at this point where we find the moral problem posed by the use of Apple ProRes.
The quality of this codec is undeniable—not in vain is it used for editing—but by requesting it and importing it into an editing program, it is possible to modify the color grading and the parameters that the editor, cinematographer, and director (not to mention the sound technician, since importing alters the original sound track) have approved as final. While we understand that festivals will respect the work of those responsible for the film, then… what need do they have to be so close to altering the final video? None. Moreover, in the filmmaking process, who decides the final quality of the film? The director, together with the cinematographer and editor, or the festival?I believe the answer should be clear, shouldn’t it? So why do festivals decide on the final quality of the H.264? Or of the export from the working files?
If a festival considers that the HD file in H.264 it has received does not have sufficient quality for screening, it only needs to communicate this to those responsible, and they will send another to replace it, if necessary (in most cases it will have already been screened at other festivals or in test screenings), but in no case would it be justified for festivals (or anyone outside the film’s production) to do post-production work with the image and sound. Here we enter into legal aspects, since festivals do not have the rights to “transform” the work (they don’t need them—it’s about seeing and enjoying the work as the authors created it), and even if this is minimal, the mere fact of requesting an intermediate codec and going through an editing program would already be altering the moral rights of the authors (according to Spanish law, the director, screenwriter, composer, and cinematographer).
If a festival wants the best quality for screenings, there are solutions created by the industry itself:
– For HD: Files with the H.264 codec (MPEG4) in Full HD 1080p or HD standard 720p. These files are provided directly by the film’s producer or distributor. Subtitles can be in .SRT or .ASS on separate tracks. And if we use the MKV container, we can give the festival the option to screen in Dolby Digital 5.1.
And if this codec seems to us not to have sufficient quality for our festival, that is why the standard format for digital cinema in 2K and 4K has been established, under the DCI standard:
– DCP: with the JPEG2000 codec for video, far superior to Apple ProRes, and PCM (uncompressed) for sound, with subtitles in .XML
In both the HD (H.264) and DCP cases, screening is done with playlists to group films in the same session. Easy, simple, and above all, with standard formats, available to everyone, on any platform, and respecting the cinematic work and its authors.