--- /dev/null
+#!/bin/sh
+
+srcdir=${0%/*}/..
+
+while read -r field equal value; do
+ case "$field $equal" in
+ ".id =")
+ eval "known_${value%,}=1"
+ ;;
+ esac
+done < $srcdir/libavcodec/codec_desc.c
+
+known_AV_CODEC_ID_NONE=1
+known_AV_CODEC_ID_FIRST_AUDIO=1
+known_AV_CODEC_ID_FIRST_SUBTITLE=1
+known_AV_CODEC_ID_FIRST_UNKNOWN=1
+known_AV_CODEC_ID_TTF=1
+known_AV_CODEC_ID_PROBE=1
+known_AV_CODEC_ID_MPEG2TS=1
+known_AV_CODEC_ID_MPEG4SYSTEMS=1
+known_AV_CODEC_ID_FFMETADATA=1
+
+in=0
+while read -r line; do
+ case "$in-$line" in
+ 0-"enum AVCodecID"*) in=1;;
+ 1-*"};"*) in=0;;
+ 1-*AV_CODEC_ID_*,*)
+ cid="${line%%[, =]*}"
+ eval "known=\$known_$cid"
+ case "$known" in
+ 1) ;;
+ *) echo "$cid missing";;
+ esac
+ ;;
+ esac
+done < $srcdir/libavcodec/avcodec.h