With this feature, it becomes possible to perform commonly
requested tasks, such as hardcoding bitmap subtitles.
This will be reverted once libavfilter has proper support
for subtitles. All the changes have the string "sub2video"
in them, it makes it easy to spot the parts.
This change introduces a basic encoder for 3GPP Timed Text subtitles,
also known as TX3G, Quicktime subtitles, or "movtext" in the existing
code.
This initial change doesn't attempt to write styling information,
and just writes the plain text of the subtitles. I intend to add
support for styles eventually, but it's challenging due to a lack
of existing players that support them.
Note that an additional change is required to the mov/mp4 muxer to
write empty subtitle packets to indicate subtitle duration.
Signed-off-by: Philip Langdale <philipl@overt.org>
This adds two protocols, but one of them is an internal implementation
detail just used as an abstraction layer/generalization in the code. The
RTMPE protocol implementation uses ffrtmpcrypt:// as an alternative to the
tcp:// protocol. This allows moving most of the lower level logic out
from the higher level generic rtmp code.
Signed-off-by: Martin Storsjö <martin@martin.st>
These filters are designed for storing and transmitting video sequences
with alpha using higher-efficiency codecs such as x264 which don't
natively support an alpha channel. 'alphaextract' takes an input stream
with an alpha channel and returns a video containing just the alpha
component as a grayscale value; 'alphamerge' takes an RGB or YUV stream
and adds an alpha channel recovered from a second grayscale stream.
Signed-off-by: Steven Robertson <steven@strobe.cc>
Signed-off-by: Stefano Sabatini <stefasab@gmail.com>
Allows to disable interaction from standard input.
Useful, for example, if ffmpeg is in the background process group.
Roughly the same result can be achieved with "ffmpeg ... < /dev/null"
but it requires a shell.
This change introduces a basic decoder for 3GPP Timed Text subtitles,
also known as TX3G, Quicktime subtitles, or "movtext" in the existing
code.
This initial change doesn't attempt to parse styling information,
and just reads the plain text of the subtitles. I intend to add
support for styles eventually, but it's challenging due to a lack
of existing players that support them.
Signed-off-by: Philip Langdale <philipl@overt.org>
This adds two protocols, but one of them is an internal implementation
detail just used as an abstraction layer/generalization in the code. The
RTMPT protocol implementation uses rtmphttp:// as an alternative to the
tcp:// protocol. This allows moving most of the lower level logic out
from the higher level generic rtmp code.
Signed-off-by: Martin Storsjö <martin@martin.st>
Add atempo audio filter for adjusting audio tempo without affecting
pitch. This filter implements WSOLA algorithm with fast cross
correlation calculation in frequency domain.
Signed-off-by: Pavel Koshevoy <pavel@homestead.aragog.com>
Signed-off-by: Stefano Sabatini <stefasab@gmail.com>