Screenshots
Libass:

ISR:

Description of the issue
Libass currently loads and renders fonts embedded in the [Fonts] section of an ASS file even if they are in WOFF or WOFF2 formats. However VSFilters (tested with MPC-HC's ISR and XY-VSFilter) don't support these and fail to load them.
libass version
0.17.4 (and older)
Is it a regression?
I don't think so.
ASS Sample
Script-embedded WOFF font:
[Script Info]
ScriptType: v4.00+
ScaledBorderAndShadow: yes
PlayResX: 1920
PlayResY: 1080
[V4+ Styles]
Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, StrikeOut, ScaleX, ScaleY, Spacing, Angle, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, Encoding
Style: Sign,Arial,120,&H00FFFFFF,&H000000FF,&H00000000,&H00000000,0,0,0,0,100,100,0,0,1,4,0,5,10,10,10,1
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:00.00,0:00:05.00,Sign,,0,0,0,,{\fnYAP0DWY7}Font
[Fonts]
fontname: woff_0.ttf
>U^'2A!"!!!!!!.U!!I!!!!!#!A!!1!!!!!!!!!!!!!!!!!!!!!!!!!!!!"05S]S!!!#0!!!!%E!!!"A
7RFI<7.N98!!!!+)!!!!.1!!!%1!B!%E:WRZ:A!!!01!!!#`!!!&#,2-5QJI:7&E!!!"W!!!!$9!!!!W
QU3\%7BI:7%!!!)=!!!!(1!!!#1&1A'#;'VU?!!!!B!!!!!,!!!!$!)!!!"M<W.B!!!"T!!!!!Q!!!!-
!K!$V'VB?(!!!!'U!!!!'!!!!#!!3!%*<G&N:1!!!M!!!!#A!!!!`"%1+B&Q<X.U!!!$9!!!!"1!!!!A
!'E!.(C=9Z"F!!,'!UQ.$-Q-\!T=$0Q-QATC$.)-]AT+$/I-WAT[$-9-ZAT7$09-TATO$.Y-`AT"$/%-
U1TR$-E-[1T:$0E-R1Q-AM;CSO9YM#+56M:"E[I?2DNA!@];M)GC+TK!6ZK*'$.1!)-=*!Q:$V!1BO7Y
1R%7)KIUYO-+)59'#+_"'DT'![1'+V8$6JC/Y9K-;2/S;'&*<NB+10/_!]FB#Q^01LG:5#['U9:I_BK1
X)HJ/[,^SU3M1A!K20K;!(C=9W"E9'"A:?2A=')!!59'.!!!"[=!5Q!!!!!!IA&1!@Y#B!!"!!!!!1!!
R`5<(6]0005!!!1!!!!!!(R7"8]!!!!!ZBNR61!!!!!"Q!.!!!!!#!!#!!!!!!!!?*RD9E!!!!!E!!-!
?*RD9'2A9(<Y\]$!Q-1!"!Z!EJ%"&4!#!$-X!=I!!!"YH'.A9G*AH-$!SM$#R-$%Q-$Q@Q'%"G*DBD.!
"A-,!RQQ-C#"3%=@019("D?'%G;(`QY-$-Q/$!>A;BA0-$5!+15'"A#-0!F$!!!!?*RD9'"A9G"A9!:C
%3$*#+::'!S!.!=1AO4='0):3P\`"\0S1+T`O`^0_4]"L"9-!/Z+#[)!!!"YH%W/P1L#1"#%PZCIW)C6
^4W"K)A76I*9"R6&/X_###'2'!5<H]#(>LQ\)2R\.TP\\8"!ETUB1>1#-J84!2VV4N>I]`9[L0B22>@J
]P'[9@W9AJQ4#8?>B$/')S`>-_MM.-UI7@'1`S.+T:Y-[4(QV7=K\[;N0\X7GZ/+.YR%D$W`5WIM@MZ7
?M*3?2=FJRTUDYW[1DN8GW*=^B>(W2]_?*RD9';!A$1'9S$*S)!'!!XH!*Y
Script-embedded WOFF2 font:
[Script Info]
ScriptType: v4.00+
ScaledBorderAndShadow: yes
PlayResX: 1920
PlayResY: 1080
[V4+ Styles]
Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, StrikeOut, ScaleX, ScaleY, Spacing, Angle, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, Encoding
Style: Sign,Arial,120,&H00FFFFFF,&H000000FF,&H00000000,&H00000000,0,0,0,0,100,100,0,0,1,4,0,5,10,10,10,1
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:00.00,0:00:05.00,Sign,,0,0,0,,{\fnYAP0DWY7}Font
[Fonts]
fontname: woff2_0.ttf
>U^'-A!"!!!!!!(E!!I!!!!!#!A!!!':!!%!!!!!!!!!!!!!!!!!!!!!!!!!!!!!"G!!2!K+#)A]!49#
*!--#QQ!"#!&A8Q()"O""AC?B\%T)J4BG<+C^3'#;!W>P@]0!!M4NH2"&5@I)MF4B;RTR-*7W"J\0PUW
(V)#C@MBY4,,YN%=]<216A08F`7A)A6*/8)KF`"=E-;PQHP[#-LH(,'+.&[LTGB)!RNOA#0$W=Z=RDZ\
F,3E4=;[)38R8K./%ML[H[P%KD`5!!1!H']>,)B-F&5O';KM2U$]4/]Q"UCI-)12'-*;!GX;*/R,F+6A
XU>:3PF3&A)!.+!$4R"`C8_!'D#.R_.K>K4JV(%I\3[C\RB5,IY_V:V00,7`Z,)[,I?Y\:'0$LIY]C\H
8+"%OG2.6`D)?`3(H,,ZS.NN@E(YYY8URB:^1ZH_-MD08J0'SQ=)""]U@^O\JEU.HE_;._$`Z.-R%$_L
$.IE%&3Z:%C1%Q%!C'23U%3<\72WV?I#)_JWX-.#1Z]0GP2YL6:_N1<;'0%T7X!_F5M=H25+24YB$DIT
>MYG%B_FB9K%)&!';QK",--3&Z(K5N>,C=2,A>!)D!HOR+<_S-:[V$2X>F6ZW=ONH?5+>YE05P&-"H"(
\1A!!!
The font extension doesn't matter, it works the same for both woff_0.woff and woff2_0.woff2.
Special Fonts
I uploaded or linked to the required font
System Information
Windows 11. Tested on mpv 0.41.0 (Libass 0.17.4), MPC-HC 2.7.1 (ISR) and VapourSynth R41 (xy-VSFilter from package xyvsf R3)
Log
No response
Additional info
No response
Screenshots
Libass:

ISR:

Description of the issue
Libass currently loads and renders fonts embedded in the
[Fonts]section of an ASS file even if they are in WOFF or WOFF2 formats. However VSFilters (tested with MPC-HC's ISR and XY-VSFilter) don't support these and fail to load them.libass version
0.17.4 (and older)
Is it a regression?
I don't think so.
ASS Sample
Script-embedded WOFF font:
Script-embedded WOFF2 font:
The font extension doesn't matter, it works the same for both
woff_0.woffandwoff2_0.woff2.Special Fonts
I uploaded or linked to the required font
System Information
Windows 11. Tested on mpv 0.41.0 (Libass 0.17.4), MPC-HC 2.7.1 (ISR) and VapourSynth R41 (xy-VSFilter from package xyvsf R3)
Log
No response
Additional info
No response