lavfi: add trim and atrim filters.

Changelog

@@ -13,6 +13,7 @@ version 10:
 - new interlace filter
 - JPEG 2000 decoder
 - new asetpts filter (same as setpts, but for audio)
+- new trim and atrim filters
 
 
 version 9:

doc/filters.texi

@@ -345,6 +345,70 @@ with a negative pts due to encoder delay.
 
 @end table
 
+@section atrim
+Trim the input so that the output contains one continuous subpart of the input.
+
+This filter accepts the following options:
+@table @option
+@item start
+Timestamp (in seconds) of the start of the kept section. I.e. the audio sample
+with the timestamp @var{start} will be the first sample in the output.
+
+@item end
+Timestamp (in seconds) of the first audio sample that will be dropped. I.e. the
+audio sample immediately preceding the one with the timestamp @var{end} will be
+the last sample in the output.
+
+@item start_pts
+Same as @var{start}, except this option sets the start timestamp in samples
+instead of seconds.
+
+@item end_pts
+Same as @var{end}, except this option sets the end timestamp in samples instead
+of seconds.
+
+@item duration
+Maximum duration of the output in seconds.
+
+@item start_sample
+Number of the first sample that should be passed to output.
+
+@item end_sample
+Number of the first sample that should be dropped.
+@end table
+
+Note that the first two sets of the start/end options and the @option{duration}
+option look at the frame timestamp, while the _sample options simply count the
+samples that pass through the filter. So start/end_pts and start/end_sample will
+give different results when the timestamps are wrong, inexact or do not start at
+zero. Also note that this filter does not modify the timestamps. If you wish
+that the output timestamps start at zero, insert the asetpts filter after the
+atrim filter.
+
+If multiple start or end options are set, this filter tries to be greedy and
+keep all samples that match at least one of the specified constraints. To keep
+only the part that matches all the constraints at once, chain multiple atrim
+filters.
+
+The defaults are such that all the input is kept. So it is possible to set e.g.
+just the end values to keep everything before the specified time.
+
+Examples:
+@itemize
+@item
+drop everything except the second minute of input
+@example
+avconv -i INPUT -af atrim=60:120
+@end example
+
+@item
+keep only the first 1000 samples
+@example
+avconv -i INPUT -af atrim=end_sample=1000
+@end example
+
+@end itemize
+
 @section channelsplit
 Split each channel in input audio stream into a separate output stream.
 
@@ -2251,6 +2315,67 @@ l.r     l.L
 @end example
 @end table
 
+@section trim
+Trim the input so that the output contains one continuous subpart of the input.
+
+This filter accepts the following options:
+@table @option
+@item start
+Timestamp (in seconds) of the start of the kept section. I.e. the frame with the
+timestamp @var{start} will be the first frame in the output.
+
+@item end
+Timestamp (in seconds) of the first frame that will be dropped. I.e. the frame
+immediately preceding the one with the timestamp @var{end} will be the last
+frame in the output.
+
+@item start_pts
+Same as @var{start}, except this option sets the start timestamp in timebase
+units instead of seconds.
+
+@item end_pts
+Same as @var{end}, except this option sets the end timestamp in timebase units
+instead of seconds.
+
+@item duration
+Maximum duration of the output in seconds.
+
+@item start_frame
+Number of the first frame that should be passed to output.
+
+@item end_frame
+Number of the first frame that should be dropped.
+@end table
+
+Note that the first two sets of the start/end options and the @option{duration}
+option look at the frame timestamp, while the _frame variants simply count the
+frames that pass through the filter. Also note that this filter does not modify
+the timestamps. If you wish that the output timestamps start at zero, insert a
+setpts filter after the trim filter.
+
+If multiple start or end options are set, this filter tries to be greedy and
+keep all the frames that match at least one of the specified constraints. To keep
+only the part that matches all the constraints at once, chain multiple trim
+filters.
+
+The defaults are such that all the input is kept. So it is possible to set e.g.
+just the end values to keep everything before the specified time.
+
+Examples:
+@itemize
+@item
+drop everything except the second minute of input
+@example
+avconv -i INPUT -vf trim=60:120
+@end example
+
+@item
+keep only the first second
+@example
+avconv -i INPUT -vf trim=duration=1
+@end example
+
+@end itemize
 @section unsharp
 
 Sharpen or blur the input video.

libavfilter/Makefile

@@ -31,6 +31,7 @@ OBJS-$(CONFIG_ASETPTS_FILTER)                += setpts.o
 OBJS-$(CONFIG_ASHOWINFO_FILTER)              += af_ashowinfo.o
 OBJS-$(CONFIG_ASPLIT_FILTER)                 += split.o
 OBJS-$(CONFIG_ASYNCTS_FILTER)                += af_asyncts.o
+OBJS-$(CONFIG_ATRIM_FILTER)                  += trim.o
 OBJS-$(CONFIG_CHANNELMAP_FILTER)             += af_channelmap.o
 OBJS-$(CONFIG_CHANNELSPLIT_FILTER)           += af_channelsplit.o
 OBJS-$(CONFIG_JOIN_FILTER)                   += af_join.o
@@ -77,6 +78,7 @@ OBJS-$(CONFIG_SETTB_FILTER)                  += vf_settb.o
 OBJS-$(CONFIG_SHOWINFO_FILTER)               += vf_showinfo.o
 OBJS-$(CONFIG_SPLIT_FILTER)                  += split.o
 OBJS-$(CONFIG_TRANSPOSE_FILTER)              += vf_transpose.o
+OBJS-$(CONFIG_TRIM_FILTER)                   += trim.o
 OBJS-$(CONFIG_UNSHARP_FILTER)                += vf_unsharp.o
 OBJS-$(CONFIG_VFLIP_FILTER)                  += vf_vflip.o
 OBJS-$(CONFIG_YADIF_FILTER)                  += vf_yadif.o

libavfilter/allfilters.c

@@ -51,6 +51,7 @@ void avfilter_register_all(void)
     REGISTER_FILTER(ASHOWINFO,      ashowinfo,      af);
     REGISTER_FILTER(ASPLIT,         asplit,         af);
     REGISTER_FILTER(ASYNCTS,        asyncts,        af);
+    REGISTER_FILTER(ATRIM,          atrim,          af);
     REGISTER_FILTER(CHANNELMAP,     channelmap,     af);
     REGISTER_FILTER(CHANNELSPLIT,   channelsplit,   af);
     REGISTER_FILTER(JOIN,           join,           af);
@@ -97,6 +98,7 @@ void avfilter_register_all(void)
     REGISTER_FILTER(SHOWINFO,       showinfo,       vf);
     REGISTER_FILTER(SPLIT,          split,          vf);
     REGISTER_FILTER(TRANSPOSE,      transpose,      vf);
+    REGISTER_FILTER(TRIM,           trim,           vf);
     REGISTER_FILTER(UNSHARP,        unsharp,        vf);
     REGISTER_FILTER(VFLIP,          vflip,          vf);
     REGISTER_FILTER(YADIF,          yadif,          vf);

tests/fate/filter-audio.mak

@@ -25,6 +25,22 @@ fate-filter-asyncts: CMD = pcm -analyzeduration 10000000 -i $(SRC) -af asyncts
 fate-filter-asyncts: CMP = oneoff
 fate-filter-asyncts: REF = $(SAMPLES)/nellymoser/nellymoser-discont.pcm
 
+FATE_ATRIM += fate-filter-atrim-duration
+fate-filter-atrim-duration: CMD = framecrc -i $(SRC) -af atrim=start=0.1:duration=0.01
+FATE_ATRIM += fate-filter-atrim-mixed
+fate-filter-atrim-mixed: CMD = framecrc -i $(SRC) -af atrim=start=0.05:start_sample=1025:end=0.1:end_sample=4411
+
+FATE_ATRIM += fate-filter-atrim-samples
+fate-filter-atrim-samples: CMD = framecrc -i $(SRC) -af atrim=start_sample=26:end_sample=80
+
+FATE_ATRIM += fate-filter-atrim-time
+fate-filter-atrim-time: CMD = framecrc -i $(SRC) -af atrim=0.1:0.2
+
+$(FATE_ATRIM): tests/data/asynth-44100-2.wav
+$(FATE_ATRIM): SRC = $(TARGET_PATH)/tests/data/asynth-44100-2.wav
+
+FATE_FILTER-$(call FILTERDEMDECENCMUX, ATRIM, WAV, PCM_S16LE, PCM_S16LE, WAV) += $(FATE_ATRIM)
+
 FATE_AFILTER-$(call FILTERDEMDECENCMUX, CHANNELMAP, WAV, PCM_S16LE, PCM_S16LE, WAV) += fate-filter-channelmap
 fate-filter-channelmap: SRC = $(TARGET_PATH)/tests/data/asynth-44100-6.wav
 fate-filter-channelmap: tests/data/asynth-44100-6.wav

tests/fate/filter-video.mak

@@ -42,6 +42,20 @@ fate-filter-setpts: CMD = framecrc -c:v pgmyuv -i $(SRC) -filter_script $(SRC_PA
 FATE_FILTER_VSYNTH-$(CONFIG_TRANSPOSE_FILTER) += fate-filter-transpose
 fate-filter-transpose: CMD = framecrc -c:v pgmyuv -i $(SRC) -vf transpose
 
+FATE_TRIM += fate-filter-trim-duration
+fate-filter-trim-duration: CMD = framecrc -i $(SRC) -vf trim=start=0.4:duration=0.05
+
+FATE_TRIM += fate-filter-trim-frame
+fate-filter-trim-frame: CMD = framecrc -i $(SRC) -vf trim=start_frame=3:end_frame=10
+
+FATE_TRIM += fate-filter-trim-mixed
+fate-filter-trim-mixed: CMD = framecrc -i $(SRC) -vf trim=start=0.2:end=0.4:start_frame=1:end_frame=3
+
+FATE_TRIM += fate-filter-trim-time
+fate-filter-trim-time: CMD = framecrc -i $(SRC) -vf trim=0:0.1
+
+FATE_FILTER_VSYNTH-$(CONFIG_TRIM_FILTER) += $(FATE_TRIM)
+
 FATE_FILTER_VSYNTH-$(CONFIG_UNSHARP_FILTER) += fate-filter-unsharp
 fate-filter-unsharp: CMD = framecrc -c:v pgmyuv -i $(SRC) -vf unsharp
 

tests/ref/fate/filter-atrim-duration

+#tb 0: 1/44100
+0,       4410,       4410,      441,     1764, 0x61e374f7

tests/ref/fate/filter-atrim-mixed

+#tb 0: 1/44100
+0,       1025,       1025,     1023,     4092, 0x78560a4c
+0,       2048,       2048,     1024,     4096, 0xc477fa99
+0,       3072,       3072,     1024,     4096, 0x3bc0f14f
+0,       4096,       4096,      315,     1260, 0xe4b26b50

tests/ref/fate/filter-atrim-samples

+#tb 0: 1/44100
+0,         26,         26,       54,      216, 0x6b376c6c

tests/ref/fate/filter-atrim-time

+#tb 0: 1/44100
+0,       4410,       4410,      710,     2840, 0x658982a3
+0,       5120,       5120,     1024,     4096, 0xfd6a0070
+0,       6144,       6144,     1024,     4096, 0x0b01f4cf
+0,       7168,       7168,     1024,     4096, 0x6716fd93
+0,       8192,       8192,      628,     2512, 0xda5ddff8

tests/ref/fate/filter-trim-duration

+#tb 0: 1/25
+0,         10,         10,        1,   152064, 0xb45c4760

tests/ref/fate/filter-trim-frame

+#tb 0: 1/25
+0,          3,          3,        1,   152064, 0xceb080b0
+0,          4,          4,        1,   152064, 0x473db652
+0,          5,          5,        1,   152064, 0x287da8e6
+0,          6,          6,        1,   152064, 0x68b47c23
+0,          7,          7,        1,   152064, 0xe9028bac
+0,          8,          8,        1,   152064, 0x28ff8026
+0,          9,          9,        1,   152064, 0x2d7c3915

tests/ref/fate/filter-trim-mixed

+#tb 0: 1/25
+0,          1,          1,        1,   152064, 0x7f5f6551
+0,          2,          2,        1,   152064, 0xc566f64a
+0,          3,          3,        1,   152064, 0xceb080b0
+0,          4,          4,        1,   152064, 0x473db652
+0,          5,          5,        1,   152064, 0x287da8e6
+0,          6,          6,        1,   152064, 0x68b47c23
+0,          7,          7,        1,   152064, 0xe9028bac
+0,          8,          8,        1,   152064, 0x28ff8026
+0,          9,          9,        1,   152064, 0x2d7c3915

tests/ref/fate/filter-trim-time

+#tb 0: 1/25
+0,          0,          0,        1,   152064, 0x6e4f89ef
+0,          1,          1,        1,   152064, 0x7f5f6551