JPEG decoding requires additional space in the bitmap buffer beyond
what is needed for the decoded pixel data. Provide a way to estimate
how much overhead is needed.
The actual overhead is sizeof(struct jpeg) + decode_buf_size, where
the latter depends on the image size and JPEG encoding used. From my
testing decode_buf_size is normally pretty small (under 5 KiB) but
looking at the code it could be large in some cases, primarily with
large images, so 32 KiB seems to be a decent compromise. Someone who
knows better about JPEG should pick a better value if that's too big.
Using a constant is obviously not the most accurate but it seems to
be the simplest option for retrofitting to existing code.
Change-Id: I573b0abb8ca2d79e43f185010487f07226edb793
- Support is limited to non-desync jpeg in id3v2 tags. Other formats (hopefully) follow in the future.
- Embedded album art takes precedence over files in album art files.
- No additional buffers are used, the jpeg is read directly from the audio file.
Flyspray: FS#11216
Author: Yoshihisa Uchida and I
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@29259 a1c6a512-1295-4272-9138-f99709370657
