lavfi: add field filter

The filter is a port of libmpcodecs/vf_field.c, since there is no common
code I relicensed it as LGPL, while keeping the original author
copyright.

3 files changed, 103 insertions, 0 deletions

diff --git a/tests/fate/avfilter.mak b/tests/fate/avfilter.mak
index b9312442d1..239fe64570 100644
--- a/tests/fate/avfilter.mak
+++ b/tests/fate/avfilter.mak
@@ -11,6 +11,7 @@ FATE_LAVFI = fate-lavfi-alphaextract_rgb                                \
              fate-lavfi-drawbox                                         \
              fate-lavfi-edgedetect                                      \
              fate-lavfi-fade                                            \
+             fate-lavfi-field                                           \
              fate-lavfi-idet                                            \
              fate-lavfi-life                                            \
              fate-lavfi-null                                            \
diff --git a/tests/lavfi-regression.sh b/tests/lavfi-regression.sh
index 703d56c1b1..76b2e5a062 100755
--- a/tests/lavfi-regression.sh
+++ b/tests/lavfi-regression.sh
@@ -111,6 +111,7 @@ do_lavfi_pixfmts(){
 do_lavfi_pixfmts "copy"    ""
 do_lavfi_pixfmts "crop"    "100:100:100:100"
 do_lavfi_pixfmts "hflip"   ""
+do_lavfi_pixfmts "field"   "field" "bottom"
 do_lavfi_pixfmts "null"    ""
 do_lavfi_pixfmts "pad"     "500:400:20:20"
 do_lavfi_pixfmts "pixdesctest" ""
diff --git a/tests/ref/lavfi/field b/tests/ref/lavfi/field
new file mode 100644
index 0000000000..3ca797a0e4
--- /dev/null
+++ b/tests/ref/lavfi/field
@@ -0,0 +1,101 @@
+0bgr                57434af4bddb691877f2400c704604eb
+0rgb                fc2ba950163aeee98590181e31fcd202
+abgr                3c78d0a72484a1ecd3cae245b9fa988c
+argb                d5057a2be412864719ffb8ba129c1f2c
+bgr0                b33c6b58b0d7bf6ce07d5a2d7c267040
+bgr24               bd6620738df19410d5df5f31e7451709
+bgr444be            219e318b7e0e05050181e71df6b9539d
+bgr444le            8354f2cf5b30de0233d302a74816649d
+bgr48be             22be50bd0aa39f07ad1b1aa57cb741ce
+bgr48le             c4b0f8057b3eac237e9228e83bdc4c66
+bgr4_byte           d4c3304b4b823a130c335379e4d3444d
+bgr555be            c3072da465233dbfc8f61dc7a9766d2c
+bgr555le            be83adcf0b802b061442f0c564fd5987
+bgr565be            bf955b9a035af0e613cf1de249f55f9d
+bgr565le            6dd85cd5e19266c53a54cbcf06d396a7
+bgr8                9669f6974f0fc1c0afa1c7d4df093c0b
+bgra                f7cabae31dd7465dab2203f45db646f8
+gray                66a09b53f7d3f79dcb6096f3ec3740c5
+gray16be            a447af6482b922c9997ac02e5d3535f1
+gray16le            c1dd0db327295898ff282d07f48c105d
+monob               1b7fb7e69a913a0a1c0dffc54e5899ea
+monow               b5d3778a054fc73d515d36f8a6bc693b
+nv12                b3829e9ae2a15349432b7efac4236068
+nv21                963cf5780e07301ff2906bf345b6d0ff
+pal8                bfedafc3bf19c2c12eeb87125833142a
+rgb0                d7481143742ff68abfbac4195edbede0
+rgb24               908d5494062c617bc87149c9daaf2167
+rgb444be            281a8f186a2726c2b31aa7e09e21c865
+rgb444le            93f9ee6265d8ad5e744ab652563f9b78
+rgb48be             0d1d60e1639edb2758ad776cb5583970
+rgb48le             c958b5e98324263e97de2bb528f5bda4
+rgb4_byte           2ec97bf65649e3d47eb6812701544593
+rgb555be            21b9138b229d4065b02d38b5b62f18d1
+rgb555le            0307ee34e562b2fb2b1c6988ae18b2b2
+rgb565be            e8f3ebcbb9a5fff000eca8a312f89782
+rgb565le            53bbd558fb0dcd82f1fad83ea855c3ad
+rgb8                67bfdd4fa88b1ab9be876f42dfc75683
+rgba                d0ebdf1495bc6b7e9d3bfbe2813a9d16
+uyvy422             a6a52504a16f09b8f2ec2405bc8190b5
+yuv410p             3feb55b1e2a385b488c82e808a12587b
+yuv411p             ab3dd8e6cf1452afe2d2e976e4726370
+yuv420p             52e26ad198368e2326bef97cdfa6a2bb
+yuv420p10be         04353bfc21e9b88cd7776e83be756742
+yuv420p10le         3f8e7167dbd12976c6ee516b8c952363
+yuv420p12be         b058ac076c8a5fe522b9fd9b8422054e
+yuv420p12le         ad0bf28e69eeb14eac5d8f9ea8b801f1
+yuv420p14be         c7a435d42f07928332ecb21a7d96ad7a
+yuv420p14le         5507e8db4e58c9517012686a7408996b
+yuv420p16be         5241d64e9fa2fd6590fd23ea0e8a6f90
+yuv420p16le         78da606f761a4fb62fdac05aa5092742
+yuv420p9be          e4bcaf5d6a7030f950b08501327f6175
+yuv420p9le          bbf80e57389578be66d4a7a12335a613
+yuv422p             e461a21995da361b88202339a2ebb879
+yuv422p10be         a3e13070215f5a016ac9bae7e7115417
+yuv422p10le         8e9e3d9adc8fdb8a0a03d79bdc31eefe
+yuv422p12be         4c339f71d79d2dac1dabc6121e1cf021
+yuv422p12le         69d336fccbe1ffa88106ea5bde0c8743
+yuv422p14be         f20c21dbfda632d26816fce27c1cb6e9
+yuv422p14le         70dddb8bdad188079a05113059d139f8
+yuv422p16be         55cfed8fa610f82b6625e16871dab235
+yuv422p16le         e2488df0f22987fe7ed12a5ef2adf835
+yuv422p9be          80fcdd7fd9cdd79632104dcc32f78b4b
+yuv422p9le          e0ec9f94c875297ee5d0546274df40e9
+yuv440p             f8e80596babcdb94378ec8bebf2dd46d
+yuv444p             572bad9e12ed53e242658fa613412279
+yuv444p10be         c5304f086afc4624d4fffb66a3cf3cb8
+yuv444p10le         d1754974b936f74028752d49413d30aa
+yuv444p12be         206d6b0fbd84d4e013b9b074cbd65135
+yuv444p12le         dc2b1bfbecba71eba50e7e4da470a8d0
+yuv444p14be         19cd2ef75ed5698898c55040e51def88
+yuv444p14le         8d47c9575d1355572ee9bfc873d46753
+yuv444p16be         3a67c28325978db734ba03b1828c15da
+yuv444p16le         c6dc275a4277fd3c65535253bb298263
+yuv444p9be          f47357cdd775fc399aeab3ae58712fb9
+yuv444p9le          e29799ecb6fac9f5b6d85bc34d248d4b
+yuva420p            82ab09bb7a3a24bf95aeb3fa9d939847
+yuva420p10be        f4559039e99ecf74a58e7063b1e7c5d3
+yuva420p10le        b1eb7df29134936450c2c312ae23a1a4
+yuva420p16be        c580495d34c6ac6e3e3b81772a0f3070
+yuva420p16le        1c49deeafb8f81e9186f3906c9b1a670
+yuva420p9be         a788d7cc6ad67ad52619a08da126569a
+yuva420p9le         c1579a5c015908f26b76480d82f6a648
+yuva422p            c162b37ce05360c47b2a2224ea0748ad
+yuva422p10be        6df70d1018e8c0c9fa377f72f49bf81b
+yuva422p10le        2eb54f20d3e5f180c539d92a75fe66e9
+yuva422p16be        1c61492076be33404894c1d3ec578d87
+yuva422p16le        1c085c9479a57eea35e74c264c947d73
+yuva422p9be         271c6cc091052731373ef5313bc76435
+yuva422p9le         b8c2e963ac35371e8aa6a05d5c252b37
+yuva444p            4a85f1f17e95829cd53c9a28928fd8eb
+yuva444p10be        d312f0d30a88fdd18e992362ea3b5f81
+yuva444p10le        d12aed62a367bc7735e59503a3cf8cc6
+yuva444p16be        ac5c17adeb0ef6730a0de1dbd1d14a1a
+yuva444p16le        41f1a82eb686d7191bdb00206f723247
+yuva444p9be         413d01385a8b008031b2ab3ef0b9eff4
+yuva444p9le         33ede0bd20bfd85489d266ac81d035d6
+yuvj420p            762dc6a157d0bee72da3e3d852668aef
+yuvj422p            8cec955c1c62b00b6798361ef82962b7
+yuvj440p            7b469444994d8b52766ee461bcb795ea
+yuvj444p            b395162325af489c465a3e6a31fbb0e7
+yuyv422             1efb17cd0a48d2e956fd574ea6f412e7