oggSlideshow(1) Manual page


OGGSLIDESHOW(1) User Manuals OGGSLIDESHOW(1)

NAME
oggSlideshow – creates slideshows from pictures

SYNOPSIS
oggSlideshow [options] picture1 [ picture2 […] ]

DESCRIPTION
oggSlideshow creates a theora video from a number of pictures in JPEG-
or PNG-format with different visual effects.

OPTIONS
-s

Sets the size of the video frame. The size is given as
x

Example: -s 320×240

-f Sets the frame rate of the video. This is given by the pictures
per second. The default frame rate is 24 pictures per second.

Example: -f 16

-o Sets the output file name of the created video. The default name
is slideshow.ogv.

Example: -o myShow.ogv

-l Sets the presentation time (length) of one picture. So if your
have 10 pictures and specify a length of 10 seconds, then your
overall video length is 1:40 (100 seconds).

Example: -l 10

-d Sets the datarate in byte per seconds for the video encoder.
This more meant to be a upper threshold. So the file may be
smaller than assumed.

Example: -d 1024000

-t Sets the presentation type, as shown above. Actually types are:

kb:
Ken Burns effect (default)

cf:
Picture crossfade for changeover

p:
Plain picture presentation

bl:
Bluring at changeover

Example: -t p

-e Enables the reframing. In case a picture does not match the
aspect ratio of the video frame, it can be “reframed”, which
means black borders are inserted. This option is only usefull
with the Ken Burns effect (option -t kb). The pictures are auto-
maticaly “reframed” with the other two slideshow types to match
the aspect ratio.

Example: -e

-r Enables the resampling to a certain value. This is really only
for experts and may not be available with newer version of
oggSlideshow.

To understand this option you need some more internal informa-
tion: The picture is loaded by the gd lib. So the transformation
from png or jpeg to a plain RGBA is done here. The second reason
for using gd is the great resizing facilities as pictures are
often much bigger than the video frame. OggSlideshow can handle
pictures from 0.5 to 2 times of the video frame width and height
best, as it uses a linear pixel interpolation. With the resizing
feature of gd, oggSlideshow reads pictures with a size “near” to
the video output size and can then operate with that picture.
This produces a very good quality output, as you can see above.

The value given with this option is the factor the picture is
read in in respect of the video frame size. When the video frame
size is 320×240 and the resample factor is 1.2 than the picture
that is read is resized to 384×288. Specially for the ken burns
effect this is important as the sliding is done on a picture
bigger than the video frame size.

EXAMPLE
oggSlideshow -l3 -tp -d1024000 -s480x320 -o demo-plain.ogv

AUTHOR
Joern Seger

Linux JULY 2009 OGGSLIDESHOW(1)

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