By Werner Ruotsalainen on Sun, 06/03/2012
UPDATE (06/19/2012): there are several new articles on competing, alternative hardware HDMI recorders. One of them is Elgato Game Capture HD, which is comparatively cheap ($200), sports both HDMI and component(!) input, is small, only requires a USB 2 connector and is compatible with both PC's and OS X Mac's. (Blackmagic Design Intensity Extreme is strictly Mac with Thunderbolt-compliant and doesn't have component input). However, it can't record 1080p signal, only 720p/1080i and can't deliver uncompressed footage to the host computer either, something that videographers wanting to built a very cheap Red One alternative really want (if you don't need uncompressed, direct footage, then, this won't affect you). I recommend THIS and THIS articles (along with the user comments).
Unless you have an HDMI recorder, which, at least up to the recent release of the comparatively cheap (currently $284 on Amazon) Blackmagic Design Intensity Extreme, wasn't at all available for Mac users (my dedicated article HERE) OR want to record your screen's content without any cables and/or in a completely mobile way (it's this group that I belong to, recording even games in the gym or when stretching before swimming – now, imagine dragging around at least a MacBook Air and the Blackmagic device to such not really electronics-friendly, humid etc. places to be able to record everything I'm doing on the iPad!), you'll want to use one of the best jailbreak programs, Display Recorder, on which I've already elaborated on in several articles (last one HERE). In the current one, I go on providing you with some expert's advice on how it should be used, particularly on the iPad 3, to get the best possible results.
I've lately used Display Recorder (DR for short) quite a lot to record some tutorial videos for Kard Combat (AppStore link; TA thread and review links), an excellent Orions (2)-alike game with, compared to Orions 2, tons of online players and existing developer support. (Time permitting, I also plan to publish a Strategy Guide for the games as I've did for all Orions episodes back in the Windows Mobile days – see for example THIS.) During these extended recording sessions, I've discovered a lot of ways you can use DR as effectively as possible.
As the game doesn't support the Retina screen of the iPad 3, I, at first, played it on my iPad 2 as DR uses the XGA (1024 * 768) recording resolution on that platform instead of 1664*1248. (Incidentally, the latter uses almost the same number of pixels (2076672) as Full HD, that is, 1920*1080 (=2073600). Probably this is the maximum number of pixels that can be encoded using the H.264 encoder; hence the non-fullscreen recording. I've also elaborated on this restriction, at least decoding-wise, in my 2K article) This has helped me to save tons of storage – the, using the default DR settings, created videos were far smaller.
Then, I started playing with the settings of DR to find out how I could completely get rid of having to use my iPad 2 for playing the game. I've found out that, by setting the scaling to Half and disable Open GL; then, it'll record into files with XGA resolution “only” – the same as is the game itself. That is, this is the most recommended setting on an iPad 3, assuming the title (game etc.) doesn't use OpenGL and/or you don't necessarily need the about 1.5 times better (1664*1248 vs. 1024*768) resolution of the non-scaled version. This is how DR's settings look like:
(click the image for the original-sized version!)
In the screenshot, I've annotated (with rectangles) the list and the switch that need to be changed / switched; note that I've also changed the recording mode to H.264 + Mic. to also record the microphone's input (second annotation with an oval; the first annotation, Rotation, will shortly be discussed). Incidentally, it's only possible to record the microphone's input and not the output of the iDevice's synthetizer.
Quality difference between the full (1664*1248) and the half-scaled (1024*768) version
I've also made some tests to find out how the odd (non-4:3 2K, as opposed to the screen of the iPad 3) resolution of the no-scaled DR recordings compare to the original screen. For this, I've used the standard ISO 12233 resolution chart (source; PNG version) I've used in all my resolution tests.
Here's a crop of how the iPad 3 renders the chart (full PNG):
Here's a crop of how DR renders the chart in full scaling (1664*1248) mode (full PNG; entire movie clip. You can even check out the video bitrate and the frame-per-second of the video / audio stream using, say, MediaInfo on OS X):
As you can see, the resolution of DR's footage is worse than that of the original even in full scaled mode (because of the lower resolution than that of the screen), let alone the half-scaled one. The latter, however, is perfectly usable for recording non-Retina screen-enabled titles.
When you upload the non-scaled (=full-resolution) output of DR to YouTube, it won't be rescaled (downsized from 1248 to 1080) to fit the Full HD height. Just select “Original” from the “Quality” drop-down menu:
In the first of the following two online YouTube videos you can also try this:
The second (half-scaled) video only offers 720p (and below) resolutions. This means the originally XGA-resolution (1024*768) video has been downsized to fit the 720 vertical pixels of the (highest-res) 720p video. This, unfortunately, results in a very bad (further) resolution drop. In the following reschart crop, you can clearly see aliasing (you can no longer count the original number of lines) occurs as early as around 600 vertical / horizontal lines per page (full screen capture HERE):
Video orientation / rotation
It's very important that you in no way touch the “Rotation” drop-down menu (the first annotation by an oval in the first screenshot above), even with games / apps that use something else than the device-optimized rotation mode.
For example, Kard Combat uses Portrait mode. This means the video you make of it will be rotated by 90 degrees. An example of this is as follows (original video recording HERE):
If you set the “Rotation” drop-down menu to Portrait, the (in-game) video will be correctly oriented but with around 2 fps only (as opposed to the 10-15 of the default one; you can also check this out in MediaInfo, which reports 1.954 fps as opposed to the 16.5 fps of the original video recorded in the default "Device" setting), which can clearly be seen in the following video (original video file HERE):
Therefore, do NOT touch this option!
Post-rotating your video is, fortunately, very easy and can be done without any need for time-consuming and quality-degrading re-encoding.
If you only plan to play it back in the desktop VLC player, go to Preferences > Video tab > Show All (button at the bottom left) > Video / Filters; here, check the „Rotate” checkbox and, then, click Rotate under Video / Filters and supply 90 (or 270) as the angle of rotation.
However, should you want to upload it to YouTube, you'll need QuickTime Pro. (Which I highly recommend – it has a lot of other nice video editing features like quick copy/paste/trim/video creation out of plain images etc.) Load the file to be rotated, press Cmd + J, select the video track, go to the “Visual Settings” tab, third or fourth button below in the Flip / rotate row. VLC won't honor this (however, you can still rotate as explained above); QuickTime, iTunes, the iOS hardware, and, last but in no way least, YouTube will. Note that HERE is a video tutorial showing all these steps. After this rotation (of the video taken in the default mode), the YouTube-uploaded version is already well-oriented (in the game) (original video file HERE):
The directory of the recorded files of DR is /var/mobile/Library/Keyboard/DisplayRecorder.
BTW, speaking of save files, Kard Combat's own one is at /private/var/mobile/Applications/<UUID>/Library/c_global.sav, should you want to play it on more than one device. (Unfortunately, there's no iCloud synching.) Then, always transfer the latest version of file to the device you plan to play the game on, and so on.