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 To get development error messages printed to stdout when something goes wrong inside the transcoder, set the BASISU_DEVEL_MESSAGES macro to 1 in basisu_transcoder.h and recompile.
 
+When transcoding video files, the `transcode_image_level()` or `transcode_slice()` methods must be called in order from first to last frame, with no frames skipped. Currently, the first image is an I-Frames, and all subsequent frames are P-Frames. We will be adding more support for periodic I-Frames and seeking eventually. (The encoder and transcoder support I-Frames anywhere, we just need more work to expose this option.)
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 ### Quick Basis file details
 
 Internally, Basis files are composed of a non-uniform texture array of one or more 2D ETC1S texture "slices". ETC1S is a simple subset of the ETC1 texture format popular on Android. ETC1S has no block flips, no 4x2 or 2x4 subblocks, and each block only uses 555 base colors. ETC1S is still 100% standard ETC1, so transcoding to ETC1 or the color block of ETC2 is a no-op. We chose ETC1S because it has the very valuable property that it can be quickly transcoded to almost any other GPU texture format at very high quality using only simple per-block operations with small 1D lookup tables. Transcoding ETC1S to BC1 usually only introduces around .3 dB Y PSNR quality loss, with less loss for ETC1S->BC7. Transcoding to PVRTC1 involves only simple block level operations to compute the endpoints, and simple per-pixel scalar operations to compute the modulation values.