lavfi: mv vf_select.c -> f_select.c

The file now contains also an audio select implementation. Also move the aselect/select documentation from video filters to the multimedia filters section.
13 years ago · c51f090ff9
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -3506,140 +3506,6 @@ scale='min(500\, iw*3/2):-1'
@end example
@end itemize
@section aselect, select
 Select frames to pass in output.
 It accepts in input an expression, which is evaluated for each input
 frame. If the expression is evaluated to a non-zero value, the frame
 is selected and passed to the output, otherwise it is discarded.
 The expression can contain the following constants:
@table @option
@item n
 the sequential number of the filtered frame, starting from 0
@item selected_n
 the sequential number of the selected frame, starting from 0
@item prev_selected_n
 the sequential number of the last selected frame, NAN if undefined
@item TB
 timebase of the input timestamps
@item pts
 the PTS (Presentation TimeStamp) of the filtered video frame,
 expressed in @var{TB} units, NAN if undefined
@item t
 the PTS (Presentation TimeStamp) of the filtered video frame,
 expressed in seconds, NAN if undefined
@item prev_pts
 the PTS of the previously filtered video frame, NAN if undefined
@item prev_selected_pts
 the PTS of the last previously filtered video frame, NAN if undefined
@item prev_selected_t
 the PTS of the last previously selected video frame, NAN if undefined
@item start_pts
 the PTS of the first video frame in the video, NAN if undefined
@item start_t
 the time of the first video frame in the video, NAN if undefined
@item pict_type @emph{(video only)}
 the type of the filtered frame, can assume one of the following
 values:
@table @option
@item I
@item P
@item B
@item S
@item SI
@item SP
@item BI
@end table
@item interlace_type @emph{(video only)}
 the frame interlace type, can assume one of the following values:
@table @option
@item PROGRESSIVE
 the frame is progressive (not interlaced)
@item TOPFIRST
 the frame is top-field-first
@item BOTTOMFIRST
 the frame is bottom-field-first
@end table
@item consumed_sample_n @emph{(audio only)}
 the number of selected samples before the current frame
@item samples_n @emph{(audio only)}
 the number of samples in the current frame
@item sample_rate @emph{(audio only)}
 the input sample rate
@item key
 1 if the filtered frame is a key-frame, 0 otherwise
@item pos
 the position in the file of the filtered frame, -1 if the information
 is not available (e.g. for synthetic video)
@item scene @emph{(video only)}
 value between 0 and 1 to indicate a new scene; a low value reflects a low
 probability for the current frame to introduce a new scene, while a higher
 value means the current frame is more likely to be one (see the example below)
@end table
 The default value of the select expression is "1".
 Some examples follow:
@example
 # select all frames in input
 select
 # the above is the same as:
 select=1
 # skip all frames:
 select=0
 # select only I-frames
 select='eq(pict_type\,I)'
 # select one frame every 100
 select='not(mod(n\,100))'
 # select only frames contained in the 10-20 time interval
 select='gte(t\,10)*lte(t\,20)'
 # select only I frames contained in the 10-20 time interval
 select='gte(t\,10)*lte(t\,20)*eq(pict_type\,I)'
 # select frames with a minimum distance of 10 seconds
 select='isnan(prev_selected_t)+gte(t-prev_selected_t\,10)'
 # use aselect to select only audio frames with samples number > 100
 aselect='gt(samples_n\,100)'
@end example
 Complete example to create a mosaic of the first scenes:
@example
 ffmpeg -i video.avi -vf select='gt(scene\,0.4)',scale=160:120,tile -frames:v 1 preview.png
@end example
 Comparing @var{scene} against a value between 0.3 and 0.5 is generally a sane
 choice.
@section setdar, setsar
 The @code{setdar} filter sets the Display Aspect Ratio for the filter
@@ -4768,6 +4634,140 @@ tools.
 Below is a description of the currently available multimedia filters.
@section aselect, select
 Select frames to pass in output.
 It accepts in input an expression, which is evaluated for each input
 frame. If the expression is evaluated to a non-zero value, the frame
 is selected and passed to the output, otherwise it is discarded.
 The expression can contain the following constants:
@table @option
@item n
 the sequential number of the filtered frame, starting from 0
@item selected_n
 the sequential number of the selected frame, starting from 0
@item prev_selected_n
 the sequential number of the last selected frame, NAN if undefined
@item TB
 timebase of the input timestamps
@item pts
 the PTS (Presentation TimeStamp) of the filtered video frame,
 expressed in @var{TB} units, NAN if undefined
@item t
 the PTS (Presentation TimeStamp) of the filtered video frame,
 expressed in seconds, NAN if undefined
@item prev_pts
 the PTS of the previously filtered video frame, NAN if undefined
@item prev_selected_pts
 the PTS of the last previously filtered video frame, NAN if undefined
@item prev_selected_t
 the PTS of the last previously selected video frame, NAN if undefined
@item start_pts
 the PTS of the first video frame in the video, NAN if undefined
@item start_t
 the time of the first video frame in the video, NAN if undefined
@item pict_type @emph{(video only)}
 the type of the filtered frame, can assume one of the following
 values:
@table @option
@item I
@item P
@item B
@item S
@item SI
@item SP
@item BI
@end table
@item interlace_type @emph{(video only)}
 the frame interlace type, can assume one of the following values:
@table @option
@item PROGRESSIVE
 the frame is progressive (not interlaced)
@item TOPFIRST
 the frame is top-field-first
@item BOTTOMFIRST
 the frame is bottom-field-first
@end table
@item consumed_sample_n @emph{(audio only)}
 the number of selected samples before the current frame
@item samples_n @emph{(audio only)}
 the number of samples in the current frame
@item sample_rate @emph{(audio only)}
 the input sample rate
@item key
 1 if the filtered frame is a key-frame, 0 otherwise
@item pos
 the position in the file of the filtered frame, -1 if the information
 is not available (e.g. for synthetic video)
@item scene @emph{(video only)}
 value between 0 and 1 to indicate a new scene; a low value reflects a low
 probability for the current frame to introduce a new scene, while a higher
 value means the current frame is more likely to be one (see the example below)
@end table
 The default value of the select expression is "1".
 Some examples follow:
@example
 # select all frames in input
 select
 # the above is the same as:
 select=1
 # skip all frames:
 select=0
 # select only I-frames
 select='eq(pict_type\,I)'
 # select one frame every 100
 select='not(mod(n\,100))'
 # select only frames contained in the 10-20 time interval
 select='gte(t\,10)*lte(t\,20)'
 # select only I frames contained in the 10-20 time interval
 select='gte(t\,10)*lte(t\,20)*eq(pict_type\,I)'
 # select frames with a minimum distance of 10 seconds
 select='isnan(prev_selected_t)+gte(t-prev_selected_t\,10)'
 # use aselect to select only audio frames with samples number > 100
 aselect='gt(samples_n\,100)'
@end example
 Complete example to create a mosaic of the first scenes:
@example
 ffmpeg -i video.avi -vf select='gt(scene\,0.4)',scale=160:120,tile -frames:v 1 preview.png
@end example
 Comparing @var{scene} against a value between 0.3 and 0.5 is generally a sane
 choice.
@section asendcmd, sendcmd
 Send commands to filters in the filtergraph.
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -54,7 +54,7 @@ OBJS-$(CONFIG_AMERGE_FILTER)                 += af_amerge.o
 OBJS-$(CONFIG_AMIX_FILTER)                   += af_amix.o
 OBJS-$(CONFIG_ANULL_FILTER)                  += af_anull.o
 OBJS-$(CONFIG_ARESAMPLE_FILTER)              += af_aresample.o
 OBJS-$(CONFIG_ASELECT_FILTER)                += vf_select.o
 OBJS-$(CONFIG_ASELECT_FILTER)                += f_select.o
 OBJS-$(CONFIG_ASENDCMD_FILTER)               += f_sendcmd.o
 OBJS-$(CONFIG_ASETNSAMPLES_FILTER)           += af_asetnsamples.o
 OBJS-$(CONFIG_ASETPTS_FILTER)                += f_setpts.o
@@ -125,7 +125,7 @@ OBJS-$(CONFIG_PAD_FILTER)                    += vf_pad.o
 OBJS-$(CONFIG_PIXDESCTEST_FILTER)            += vf_pixdesctest.o
 OBJS-$(CONFIG_REMOVELOGO_FILTER)             += bbox.o lswsutils.o lavfutils.o vf_removelogo.o
 OBJS-$(CONFIG_SCALE_FILTER)                  += vf_scale.o
 OBJS-$(CONFIG_SELECT_FILTER)                 += vf_select.o
 OBJS-$(CONFIG_SELECT_FILTER)                 += f_select.o
 OBJS-$(CONFIG_SENDCMD_FILTER)                += f_sendcmd.o
 OBJS-$(CONFIG_SETDAR_FILTER)                 += vf_aspect.o
 OBJS-$(CONFIG_SETFIELD_FILTER)               += vf_setfield.o
--- a/libavfilter/vf_select.c
+++ b/libavfilter/vf_select.c