idet.sh: An alternative to ildetect.sh.

This script uses ffmpeg's "idet" filter for interlace detection. In the
long run this should replace ildetect.sh+ildetect.sh.

1 files changed, 161 insertions, 0 deletions

diff --git a/TOOLS/idet.sh b/TOOLS/idet.sh
new file mode 100755
index 0000000000..8e1580cbb8
--- /dev/null
+++ b/TOOLS/idet.sh
@@ -0,0 +1,161 @@
+#!/bin/sh
+
+case "$0" in
+    */*)
+        MYDIR=${0%/*}
+        ;;
+    *)
+        MYDIR=.
+        ;;
+esac
+
+: ${MPV:=mpv}
+: ${ILDETECT_MPV:=$MPV}
+: ${ILDETECT_MPV:=$MPV}
+: ${ILDETECT_MPVFLAGS:=--start=35% --length=35}
+: ${ILDETECT_DRY_RUN:=}
+: ${ILDETECT_QUIET:=}
+: ${ILDETECT_RUN_INTERLACED_ONLY:=}
+: ${ILDETECT_FORCE_RUN:=}
+: ${MAKE:=make}
+
+# exit status:
+# 0 progressive
+# 1 telecine
+# 2 interlaced
+# 8 unknown
+# 16 detect fail
+# 17+ mpv's status | 16
+
+testfun()
+{
+    $ILDETECT_MPV "$@" \
+        --vf=lavfi="[idet]" --msg-level ffmpeg=v \
+        --o= --vo=null --no-audio --untimed \
+        $ILDETECT_MPVFLAGS \
+        | { if [ -n "$ILDETECT_QUIET" ]; then cat; else tee /dev/stderr; fi } \
+        | grep "Parsed_idet_0: Multi frame detection: " | tail -n 1
+}
+
+judge()
+{
+    out=`testfun "$@"`
+
+    tff=${out##* TFF:}; tff=${tff%% *}
+    bff=${out##* BFF:}; bff=${bff%% *}
+    progressive=${out##* Progressive:}; progressive=${progressive%% *}
+    undetermined=${out##* Undetermined:}; undetermined=${undetermined%% *}
+
+    case "$tff$bff$progressive$undetermined" in
+        *[!0-9]*)
+            echo >&2 "ERROR: Unrecognized idet output: $out"
+            exit 16
+            ;;
+    esac
+
+    interlaced=$((bff + tff))
+    determined=$((interlaced + progressive))
+
+    if [ $undetermined -gt $determined ] || [ $determined -lt 250 ]; then
+        echo >&2 "ERROR: Less than 50% or 250 frames are determined."
+        [ -n "$ILDETECT_FORCE_RUN" ] || exit 8
+        echo >&2 "Assuming interlacing."
+        if [ $tff -gt $((bff * 10)) ]; then
+            verdict=interlaced-tff
+        elif [ $bff -gt $((tff * 10)) ]; then
+            verdict=interlaced-bff
+        else
+            verdict=interlaced
+        fi
+    elif [ $((interlaced * 20)) -gt $progressive ]; then
+        # At least 5% of the frames are interlaced!
+        if [ $tff -gt $((bff * 10)) ]; then
+            verdict=interlaced-tff
+        elif [ $bff -gt $((tff * 10)) ]; then
+            verdict=interlaced-bff
+        else
+            echo >&2 "ERROR: Content is interlaced, but can't determine field order."
+            [ -n "$ILDETECT_FORCE_RUN" ] || exit 8
+            echo >&2 "Assuming interlacing with default field order."
+            verdict=interlaced
+        fi
+    else
+        # Likely progrssive.
+        verdict=progressive
+    fi
+
+    echo "$verdict"
+}
+
+judge "$@"
+case "$verdict" in
+    progressive)
+        [ -n "$ILDETECT_DRY_RUN" ] || \
+            [ -n "$ILDETECT_RUN_INTERLACED_ONLY" ] || \
+            $ILDETECT_MPV "$@"
+        r=$?
+        [ $r -eq 0 ] || exit $(($r | 16))
+        exit 0
+        ;;
+    interlaced-tff)
+        judge "$@" --vf-pre=pullup --field-dominance=top
+        case "$verdict" in
+            progressive)
+                [ -n "$ILDETECT_DRY_RUN" ] || \
+                    $ILDETECT_MPV "$@" --vf-pre=pullup --field-dominance=top
+                r=$?
+                [ $r -eq 0 ] || exit $(($r | 16))
+                exit 1
+                ;;
+            *)
+                [ -n "$ILDETECT_DRY_RUN" ] || \
+                    $ILDETECT_MPV "$@" --vf-pre=yadif --field-dominance=top
+                r=$?
+                [ $r -eq 0 ] || exit $(($r | 16))
+                exit 2
+                ;;
+        esac
+        ;;
+    interlaced-bff)
+        judge "$@" --vf-pre=pullup --field-dominance=bottom
+        case "$verdict" in
+            progressive)
+                [ -n "$ILDETECT_DRY_RUN" ] || \
+                    $ILDETECT_MPV "$@" --vf-pre=pullup --field-dominance=bottom
+                r=$?
+                [ $r -eq 0 ] || exit $(($r | 16))
+                exit 1
+                ;;
+            *)
+                [ -n "$ILDETECT_DRY_RUN" ] || \
+                    $ILDETECT_MPV "$@" --vf-pre=yadif --field-dominance=bottom
+                r=$?
+                [ $r -eq 0 ] || exit $(($r | 16))
+                exit 2
+                ;;
+        esac
+        ;;
+    interlaced)
+        judge "$@" --vf-pre=pullup
+        case "$verdict" in
+            progressive)
+                [ -n "$ILDETECT_DRY_RUN" ] || \
+                    $ILDETECT_MPV "$@" --vf-pre=pullup
+                r=$?
+                [ $r -eq 0 ] || exit $(($r | 16))
+                exit 1
+                ;;
+            *)
+                [ -n "$ILDETECT_DRY_RUN" ] || \
+                    $ILDETECT_MPV "$@" --vf-pre=yadif
+                r=$?
+                [ $r -eq 0 ] || exit $(($r | 16))
+                exit 2
+                ;;
+        esac
+        ;;
+    *)
+        echo >&2 "ERROR: Internal error."
+        exit 16
+        ;;
+esac