some renderers may limit output to 72 and use a 3 space indent; this
avoids overflowing into the margin
Change-Id: Iaf4e8b71be27ef00fccd1d82b79bf96c01040f10
these were intended as an extension point, but in this version of the
spec they're not defined. if they ever were used leaving them as SHOULD
could result in a source of incompatibility.
Change-Id: I1376ab7abe7d955ae335106f2faebc217dac77cd
for compatibility SHOULDs are left as is with some additional
description given of behavior if the recommendation is ignored.
Change-Id: I7a25b1a6fd9f9594390c30fce3af5ca17c3158c0
this avoids presenting it in the description of a chunk where it could
appear it was defining an element of the diagram
Change-Id: I51b2c2a0dcecb4fc130711ad37c884a434920ecd
Note the fourth character is an ASCII space to avoid confusion.
Also update the FourCC definition to mention that they're case
sensitive.
Change-Id: I87d0cbcf06e7c25bf2b33419b4c8c891adb82a8a
Use the correct number of lines for fixed width entries like
ChunkHeader(). ':' is used instead of '|' for variable length entries.
Bug: webp:546
Change-Id: I6ec60af674c0777d5ea6ae99c8aa3c7854ddd9f9
Fixed: webp:546
RFC 2119 was updated by RFC 8174; use the text from there
+ change INFORMATIVE to informative to avoid confusion with the key
words in the RFCs
Change-Id: I0a3fe9dc48d284e7ac95633896ffb855ecd1a229
Break the main README into into multiple pages in the doc/ directory,
except for the tests, swig and webp_js docs which are in the corresponding
directories.
The webp mux doc is merged into the API doc and the tools doc.
Change-Id: Ia407617dd88094f4662841d37947cfef80799914
- prefer Exif to EXIF when not referring to the chunk
- normalize use of code format for canvas / frame width & height
Change-Id: I7fc9e87baeb5d8e719274680ce621dcb078a985f
- prefer https
- metadataworkinggroup.org/com seem to be offline; the web archive link
was obtained from exiftool: https://exiftool.org/TagNames/MWG.html
- fix kramdown link, rubyforge has been gone a long time
- fix png/zlib links
Bug: webp:544
Bug: b/202302177
Change-Id: Id69de4553e7baf00393f12a2c1acb262443a1a93
to https://datatracker.ietf.org/doc/html/... the http tools.ietf.org
links redirect here sometimes, in other cases they 404.
Bug: webp:544
Change-Id: I900972070d6c5659c45a86a89e78b870f42fe5bc
unknown chunks as a group are well defined in the text
+ remove the Note about stable features as it matched the list given;
there are no WIP features for the format
Change-Id: I11a4de39f9d203b815879f0e9dea9c45b2ae6ff6
replace with more inclusive terms or remove the comment entirely if the
meaning was already clear.
Bug: webp:507
Change-Id: Ica3bbf751ebf79f6668df6e6209af770248ff4ca
the interpretation of a 0 duration depends on the implementation;
merging of multiple frames isn't guaranteed, some may enforce a minimum
duration.
BUG=webp:380
Change-Id: Idf592049d2092e4cc5cfb2e4c59ddbc91bd52f9c
partially normalize indent, vertical whitespace and capitalization with
the copy used on developers.google.com/speed/webp
Change-Id: I8044418eeb9eaf5bd5c799675c74f6f845d503d6
at the beginning of the loop there's an implicit clear of the entire
canvas to the background (or application defined) color. this avoids
adding the final composited frame to the first.
Change-Id: Ia3a52cf4482c6176334a5c9c99a0ddd07d1776e7
Marking certain frames as "do not blend" helps avoiding alpha-blending
at decode/render time.
It also helps inserting I-frames (frames which can be independently
decoded) into the animation.
Change-Id: Iaa222805db88d2f1c81104ce9d882e7c7ff8cfdb
- Add a note that disposal only applies to the frame rectangle
- Add the formula for alpha-blending.
- Note that alpha-blending would occur for the common rectangle
- Also note the case when both color profile and disposal are
present.
Change-Id: I214787dd64453edf3b0cdaff3951015281a32ee4
- 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
- Add details about the VP8L chunk support.
- Also add new example bitsteams containing VP8L chunk.
- Add back a section describing the VP8 chunk.
- Restrict some fields to 16 or 24 bits instead of 32 bits.
- Fields whose values are always positive are stored 1-based
instead of 0-based.
- Unknown chunks can only occur at certain places in the file.
- Remove the restriction for some fields to be divisible by 32 or 16.
Instead they are restricted to be even.
- Add a restriction for (canvas_width * canvas_height) product.
- Add 3 bits for rotation & symmetry in VP8X flags.
- Add some new example layouts.
- Add/clarify some nitty-gritties throughout the doc.
- Use the terms frame/tile more consistently and logically.
- Update related TODOs.
Change-Id: I611c1f58ecc3ee87546ca31bad1609376fad251e
No further experiments are to be expected, so this is quite the
final format so far, pending supplemental feedbacks.
Change-Id: I2a3de025c90b7bb5fdd8792b2b2ccdc2e3753f56
