This function is always called with a non-negative argument, so
those special cases are not needed. In the places the argument
might be zero, the return value for a zero argument does not matter
since it would then be used to scale an array full of zeros.
Signed-off-by: Mans Rullgard <mans@mansr.com>
Note that the symbols used to run the hardware decoder in asynchronous mode
have been marked deprecated and will be dropped at a future version bump.
Signed-off-by: Diego Biurrun <diego@biurrun.de>
DVD subtitles packets can only encode a single rectangle:
if there are several, copy them into a big transparent one.
DVD subtitles rely on an external 16-colors palette:
use a reasonable default one, stored in the private context,
and encode it into the extradata, as specified by Matroska.
TODO: allow to change the palette with an option.
Each packet can use four colors out of the global palette.
The old logic was to map transparent colors to the color 0
and all other colors to 3, 2, 1, cyclically in descending
frequency order, completely disregarding the original color.
Select the "best" four colors from the global palette, according
to heuristics based on frequency, opacity and brightness, and
arrange them in standard DVD order: background, foreground,
outline, other.
TODO: select the alpha value more finely; see if CHG_COLCON can
allow more than 4 colors per packet.
Reference:
http://dvd.sourceforge.net/dvdinfo/spu.html
With these changes, dvdsubenc can be used to transcode DVB subtitles
and get a very decent result.
Note that the symbols used to run the hardware decoder in asynchronous mode
has been marked as deprecated and will be dropped at a future version dump.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This fixes two issues preventing suncc from building this code.
The undocumented 'a' operand modifier, causing gcc to omit a $ in
front of immediate operands (as required in addresses), is not
supported by suncc. Luckily, the also undocumented 'c' modifer
has the same effect and is supported.
On some asm statements with a large number of operands, suncc for no
obvious reason fails to correctly substitute some of the operands.
Fortunately, some of the operands in these statements are plain
numbers which can be inserted directly into the code block instead
of passed as operands.
With these changes, the code builds correctly with both gcc and
suncc.
Signed-off-by: Mans Rullgard <mans@mansr.com>
This code contains a C array of addresses of labels defined in
inline asm. To do this, the names must be declared as external
in C. The declared type does not matter since only the address is
used, and for some reason, the author of the code used the 'void'
type despite taking the address of a void expression being invalid.
Changing the type to char, a reasonable choice since the alignment
of the code labels cannot be known or guaranteed, eliminates gcc
warnings and allows building with suncc.
Signed-off-by: Mans Rullgard <mans@mansr.com>
many branches and cases of scale_vector are irrelevant for the case here
and by inlining they can be reliably removed.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
It appears someone thinks this special case can be reached
Well, it cannot, thus not only do we not need to optimize it
we dont need it at all
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Although a reasonable compiler will probably optimise out the
actual store and load, this operation still implies a truncation
to 16 bits which the compiler will probably not realise is not
necessary here.
Signed-off-by: Mans Rullgard <mans@mansr.com>
Writing the scaled excitation to a scratch buffer (borrowing the
'audio' array) instead of modifying it in place avoids the need
to save and restore the unscaled values.
Signed-off-by: Mans Rullgard <mans@mansr.com>