From 20ead3290f5464edcbbe6209fbcd102684b8696a Mon Sep 17 00:00:00 2001 From: James Zern Date: Thu, 12 Jul 2012 19:19:39 -0700 Subject: [PATCH] doc/webp-container-spec: light cosmetics - provide anchor links to the bitstream chunks referenced in the extended format section - remove some unnecessary parenthetical notation and add some consistency to various chunk element definitions Change-Id: Ifd946fee81b36e4e555399555a2a58c853fdc3b7 --- doc/webp-container-spec.txt | 31 ++++++++++++++++--------------- 1 file changed, 16 insertions(+), 15 deletions(-) diff --git a/doc/webp-container-spec.txt b/doc/webp-container-spec.txt index 6bf560ca..19ef5679 100644 --- a/doc/webp-container-spec.txt +++ b/doc/webp-container-spec.txt @@ -453,21 +453,21 @@ Frame Y: 24 bits (_uint24_) Frame Width Minus One: 24 bits (_uint24_) : The _1-based_ width of the frame. - The Frame Width is '1 + Frame Width Minus One' + The frame width is '1 + Frame Width Minus One' Frame Height Minus One: 24 bits (_uint24_) : The _1-based_ height of the frame. - The Frame Height is '1 + Frame Height Minus One' + The frame height is '1 + Frame Height Minus One' Frame Duration Minus One: 24 bits (_uint24_) -: _1-based_ time to wait before displaying the next frame, in 1 millisecond +: The _1-based_ time to wait before displaying the next frame, in 1 millisecond units. The actual duration is '1 + Frame Duration Minus One' milliseconds. For images that are animations, this chunk contains information about a single -frame, and describes the (optional) alpha chunk and the bitstream chunk that -follows it. If the _Animation flag_ is not set and this chunk is present, +frame, and describes the optional alpha chunk and the bitstream chunk that +follow it. If the _Animation flag_ is not set and this chunk is present, it SHOULD be ignored. @@ -485,14 +485,14 @@ it SHOULD be ignored. Tile X: 24 bits (_uint24_) -: X coordinate of the upper left corner of the tile is `Tile X * 2` +: The X coordinate of the upper left corner of the tile is `Tile X * 2` Tile Y: 24 bits (_uint24_) -: Y coordinate of the upper left corner of the tile is `Tile Y * 2` +: The Y coordinate of the upper left corner of the tile is `Tile Y * 2` For images that contain tiling, this chunk contains information about a single -tile and describes the (optional) alpha chunk and bitstream chunk that follow +tile and describes the optional alpha chunk and the bitstream chunk that follow it. If the _Tile flag_ is not set and this chunk is present, it SHOULD be ignored. @@ -584,17 +584,17 @@ However, a frame/tile containing a 'VP8L' chunk SHOULD NOT contain this chunk. **Rationale**: the transparency information of a frame/tile is already part of the 'VP8L' chunk. -The alpha channel data is losslessly stored as raw data (when +The alpha channel data is stored as uncompressed raw data (when compression method is '0') or compressed using the lossless format (when the compression method is '1'). * Raw data: consists of a byte sequence of length width * height, - containing all the 8bit transparency values in scan order. + containing all the 8-bit transparency values in scan order. * Lossless format compression: the byte sequence is a compressed image-stream (as described in the [WebP Lossless Bitstream Format] - [webpllspec]) of implicit dimension width x height. (That is, this - image-stream does NOT contain any headers describing the image dimension). + [webpllspec]) of implicit dimension width x height. That is, this + image-stream does NOT contain any headers describing the image dimension. **Rationale**: the dimension is already known from other sources, so storing it again would be redundant and error-prone. @@ -605,7 +605,7 @@ compression method is '0') or compressed using the lossless format of the ARGB quadruplet. **Rationale**: the green channel is allowed extra transformation - steps in the specification -unlike the other channels- that can + steps in the specification -- unlike the other channels -- that can improve compression. #### Bitstream (VP8/VP8L) @@ -619,8 +619,9 @@ A bitstream chunk may be either (i) a VP8 chunk, using "VP8 " (note the significant fourth-character space) as its tag _or_ (ii) a VP8L chunk , using "VP8L" as its tag. -The formats of VP8 and VP8L chunks are as described in sections _Simple file -format (lossy)_ and _Simple file format (lossless)_ respectively. +The formats of VP8 and VP8L chunks are as described in sections +[Simple file format (lossy)](#simple-file-format-lossy) +and [Simple file format (lossless)](#simple-file-format-lossless) respectively. #### Color profile