We aim for the best compromise of the following values, no matter how long it takes:

• Quality: As near perfect as possible.
• Size: As small as possible.
• Information: The video content must label the movie as tool-assisted, to prevent misconceptions from occurring. A pointer to the TASVideos website is provided because it is currently the best source of TAS-related information in the Internet.
• Copyright: The video content must label the player by name, and the TASVideos website as the source. This information should be presented so prominently that it cannot be clipped out from the movie by video editing without extraordinary effort.
• Pleasantness: Annoy the audience as little as possible. Provide a game video as undisturbed as possible.

1. Preserving all interesting video information (color, brightness, animation, movement), and
2. Having as small a file size as possible.

Other codecs may be permissible, so long as they are freely available for all operating systems; it is strongly recommended that you consult a publisher or admin before doing so.

It is highly recommended that you experiment with different settings when encoding; a great deal of settings impact file size and visual quality. In particular, bit rate is not the only thing that affects the visual quality!

See tips below.

For Ogg Vorbis, simply use -q1, which results in an average bitrate of approximately 70–80 kbps.

For AAC, use Nero's AAC encoder (the current preferred choice by the site) and -q 0.25; this will normally produce HE-AAC (sound quality at effectively double the nominal bitrate) with bitrates from 32-64 kbps depending on the platform.

Note: For all CD-based games that use Red Book audio, bitrate may be additionally raised to preserve quality.

Furthermore, you may (and should) adjust the bitrates as needed, depending on the properties of the sound in the particular game.

The EmulatorResources/MakingAVI page contains links on how to configure various emulators for video/audio capture.

Use of the emulator's built-in video dumping automatically satisfies this requirement.

• For NES and SNES, the resolution must be 256x224 or 256x240 (or 512x448 in the case of the SNES HiRes mode).
• For GBA, the resolution must be 240x160.
• For GB/SGB/CGB/GG, the resolution must be 160x144.
• For SMS, the resolution must be 256x192.
• For Genesis, the resolution must be 320x224, 320x240, 256x224 or 256x240 (the latter two are only for games that use the low resolution mode for the entirety of them, such as Shining Force, you will need to crop the borders from the sides assuming you have the aspect correction turned off in Gens; games that use a mix of the two resolution modes should let Gens dump an AVI with the stretched screen anyway).
• For N64/PSX, the resolution can be 320x240 or greater (see below).

When using the emulator's built-in video dumping, this requirement is automatically satisfied.

For those those consoles which are intended to be displayed on a TV or on CRT monitors, the MKV/MP4 must specify a display aspect ratio of 4:3.
Handhelds don't need AR correction, because their resolution is always fixed to match the display matrix pixel-for-pixel without any kind of stretching involved. Thus, any AR that doesn't match the native resolution will distort the image.

In the case of N64, and 3D games on PSX and Saturn, these extra quality requirements must be met:

• The anti-aliasing, anisotropic filtering, and other settings must be at highest possible quality. Neither the edges nor the interiors of polygons must appear jagged.

Logo

Subtitles

  Title in hh:mm:ss.ss
  by PlayerName
  Rerecord count: number

  This is a tool-assisted recording.
  For details, visit http://TASVideos.org/

1. Video has incorrect resolution or aspect ratio information
2. Quality is below that of current publications (where visual quality is roughly equal, smaller encodes are preferred)
3. Bad audio-video sync or drift (e.g. audio lags incrementally behind the video)
4. Poorly placed or incomplete subtitles (overlaps action, does not contain all relevant information such as site information, etc.)
5. Unacceptable logo (does not contain site information or distracts unnecessarily from said information, or is too long)

• Constant rate factor 20 (--crf 20) is considered the site standard for video quality; it is recommended unless this provides an unacceptably large bitrate.
  • Good average bitrates vary between 140-250 kbit/s for NES, SMS or Game Boy games and 200-600 kbit/s for other consoles, depending on the video content. Some Genesis games and most N64 and PSX games may exceed this.
  • If you are aiming for a specific bit-rate, use multi-pass encoding. It nearly always improves the quality-to-size ratio.
• Use the best motion detection settings you can afford. Our expert encoders normally use exhaustive searches (esa or tesa) with range settings around 64 (some encodes have used up to 128 for tougher to encode games where the file size needs to be crunched down even further to keep inside the site's size-to-length ratio limit). This slows down the encoding speed but the size and quality benefits are very much worth it.
• Use 15 or 16 reference frames (--ref).
• Use maximum subpixel refinement setting if your game uses subpixel motion (N64 uses always, SNES sometimes, NES never). If it doesn't, you don't need to use the maximum setting, though, again, the quality and size benefits are usually worth it if you don't mind slowing down the encoding speed.
• Use bframes, which almost always reduce video size.
• Do not set the keyint value too high, as this reduces the ability to seek in the video and inconveniences viewers. The default is 250; values higher than 600 are discouraged. Most published encodes use either 600 or 300.
• Do not use "noise reduction". Emulators do not simulate antenna or tape signal degradation, so there's no point in trying to reduce it.

For some data on tuning x264's more relevant settings, see this thread.

For polygon-based platforms (N64, PSX, Saturn, and some DS games), the following will help improve visual quality:

• Use the maximum anti-aliasing setting.
• Use the maximum full-screen anti-aliasing setting (FSAA).
• Use the maximum anisotropic filtering setting.
• Ensure that in your display card settings, there is no color-correction/skew curve active.
• Record the movie at a high resolution (such as 1280x960), then downscale it into 320x240 with a lanczos scaler before or when encoding it. Yes, it will drastically slow down the sampling, but the quality difference is worth it.
  • When capturing at higher resolutions, use integer ratios so that the image won't be unnecessarily blurred upon downscaling. For example, N64's native resolution is 320x240, so capture at 640x480, 960x720, or 1280x960, and so on.

For more info and examples on antialiasing settings, see this thread.

• EmulatorResources/MakingAVI
• Encoder's Corner forum