From 576844fd697e715ca1ab22521160a40e89a47c39 Mon Sep 17 00:00:00 2001 From: Rich Geldreich Date: Tue, 26 May 2020 00:17:00 -0400 Subject: [PATCH] Update basis_spec.txt --- spec/basis_spec.txt | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/spec/basis_spec.txt b/spec/basis_spec.txt index da9ffb5..95bab7a 100644 --- a/spec/basis_spec.txt +++ b/spec/basis_spec.txt @@ -386,7 +386,7 @@ The second bit of this section indicates if "hybrid" global/local selector codebooks are used. Hybrid codebooks are not supported either, so this bit should always be 0. -The third bit indicates of the selector codebook has been sent in raw form +The third bit indicates if the selector codebook has been sent in raw form (uncompressed). If it's set, each selector is sent as four 8-bit bytes. Each byte corresponds to four 2-bit ETC1S selectors. The first selector of each group of 4 selectors starts at the LSB (least significant bit) of each byte, and is @@ -396,7 +396,8 @@ If the third bit is 0, the selectors have been DPCM coded with Huffman coding. The "delta_selector_pal_model" Huffman table will immediately follow the third bit, and is stored using the procedure outlined in section 6.0. -Here is the DPCM decoding procedure for selector codebooks: +Immediately following the Huffman table is the compressed selector codebook. +Here is the DPCM decoding procedure: uint8_t prev_bytes[4] = { 0, 0, 0, 0 };