diff --git a/README.md b/README.md
index f487de2f..31d0fdc9 100644
--- a/README.md
+++ b/README.md
@@ -3225,6 +3225,8 @@ enable [smb](#smb-server) support (**not** recommended): `impacket==0.13.0`
 
 to install FFmpeg on Windows, grab [a recent build](https://www.gyan.dev/ffmpeg/builds/ffmpeg-git-full.7z) -- you need `ffmpeg.exe` and `ffprobe.exe` from inside the `bin` folder; copy them into `C:\Windows\System32` or any other folder that's in your `%PATH%`
 
+if your ffmpeg/ffprobe binaries have nonstandard names -- such as `ffmpeg8` (macports) -- set environment variables `PRTY_FFMPEG_BIN` and `PRTY_FFPROBE_BIN` to the corret name (or full path)
+
 
 ### dependency chickenbits
 
diff --git a/copyparty/mtag.py b/copyparty/mtag.py
index 65dcd9b8..c25d4538 100644
--- a/copyparty/mtag.py
+++ b/copyparty/mtag.py
@@ -46,24 +46,33 @@ except:
     HAVE_MUTAGEN = False
 
 
-def have_ff(scmd: str) -> bool:
-    if ANYWIN:
-        scmd += ".exe"
+def have_ff(name: str) -> bool:
+    uname = name.upper()
+    if os.environ.get("PRTY_NO_" + uname):
+        return b""
+
+    ebin = os.environ.get("PRTY_%s_BIN" % (uname,))
+    try:
+        bcmd = (ebin or name).encode("utf-8")
+    except:
+        bcmd = ebin or name
+
+    if ANYWIN and not ebin:
+        bcmd += b".exe"
 
     if PY2:
-        print("# checking {}".format(scmd))
-        acmd = (scmd + " -version").encode("ascii").split(b" ")
+        print("# checking {}".format(bcmd))
         try:
-            sp.Popen(acmd, stdout=sp.PIPE, stderr=sp.PIPE).communicate()
-            return True
+            sp.Popen([bcmd, b"-version"], stdout=sp.PIPE, stderr=sp.PIPE).communicate()
+            return bcmd
         except:
-            return False
+            return b""
     else:
-        return bool(shutil.which(scmd))
+        return shutil.which(bcmd) or b""
 
 
-HAVE_FFMPEG = not os.environ.get("PRTY_NO_FFMPEG") and have_ff("ffmpeg")
-HAVE_FFPROBE = not os.environ.get("PRTY_NO_FFPROBE") and have_ff("ffprobe")
+HAVE_FFMPEG = have_ff("ffmpeg")
+HAVE_FFPROBE = have_ff("ffprobe")
 
 CBZ_PICS = set("png jpg jpeg gif bmp tga tif tiff webp avif jxl".split())
 CBZ_01 = re.compile(r"(^|[^0-9v])0+[01]\b")
@@ -219,7 +228,7 @@ def ffprobe(
 ) -> tuple[dict[str, tuple[int, Any]], dict[str, list[Any]], list[Any], dict[str, Any]]:
     # ffprobe -hide_banner -show_streams -show_format --
     cmd = [
-        b"ffprobe",
+        HAVE_FFPROBE,
         b"-hide_banner",
         b"-show_streams",
         b"-show_format",
diff --git a/copyparty/th_srv.py b/copyparty/th_srv.py
index 21896a04..0153bf0f 100644
--- a/copyparty/th_srv.py
+++ b/copyparty/th_srv.py
@@ -860,7 +860,7 @@ class ThumbSrv(object):
         bscale = scale.format(*list(res)).encode("utf-8")
         # fmt: off
         cmd = [
-            b"ffmpeg",
+            HAVE_FFMPEG,
             b"-nostdin",
             b"-v", b"error",
             b"-hide_banner"
@@ -1001,7 +1001,7 @@ class ThumbSrv(object):
 
         # fmt: off
         cmd = [
-            b"ffmpeg",
+            HAVE_FFMPEG,
             b"-nostdin",
             b"-v", b"error",
             b"-hide_banner",
@@ -1080,7 +1080,7 @@ class ThumbSrv(object):
 
             # fmt: off
             cmd = [
-                b"ffmpeg",
+                HAVE_FFMPEG,
                 b"-nostdin",
                 b"-v", b"error",
                 b"-hide_banner",
@@ -1112,7 +1112,7 @@ class ThumbSrv(object):
 
         # fmt: off
         cmd = [
-            b"ffmpeg",
+            HAVE_FFMPEG,
             b"-nostdin",
             b"-v", b"error",
             b"-hide_banner",
@@ -1148,7 +1148,7 @@ class ThumbSrv(object):
 
         # fmt: off
         cmd = [
-            b"ffmpeg",
+            HAVE_FFMPEG,
             b"-nostdin",
             b"-v", b"error",
             b"-hide_banner",
@@ -1177,7 +1177,7 @@ class ThumbSrv(object):
 
         # fmt: off
         cmd = [
-            b"ffmpeg",
+            HAVE_FFMPEG,
             b"-nostdin",
             b"-v", b"error",
             b"-hide_banner",
@@ -1212,7 +1212,7 @@ class ThumbSrv(object):
 
         # fmt: off
         cmd = [
-            b"ffmpeg",
+            HAVE_FFMPEG,
             b"-nostdin",
             b"-v", b"error",
             b"-hide_banner",
@@ -1273,7 +1273,7 @@ class ThumbSrv(object):
 
         # fmt: off
         cmd = [
-            b"ffmpeg",
+            HAVE_FFMPEG,
             b"-nostdin",
             b"-v", b"error",
             b"-hide_banner",
@@ -1314,7 +1314,7 @@ class ThumbSrv(object):
 
         # fmt: off
         cmd = [
-            b"ffmpeg",
+            HAVE_FFMPEG,
             b"-nostdin",
             b"-v", b"error",
             b"-hide_banner",
@@ -1340,7 +1340,7 @@ class ThumbSrv(object):
             self.log("conv2 caf-transcode; dur=%d sz=%d q=%s" % (dur, sz, zs), 6)
             # fmt: off
             cmd = [
-                b"ffmpeg",
+                HAVE_FFMPEG,
                 b"-nostdin",
                 b"-v", b"error",
                 b"-hide_banner",
@@ -1361,7 +1361,7 @@ class ThumbSrv(object):
             self.log("conv2 caf-remux; dur=%d sz=%d" % (dur, sz), 6)
             # fmt: off
             cmd = [
-                b"ffmpeg",
+                HAVE_FFMPEG,
                 b"-nostdin",
                 b"-v", b"error",
                 b"-hide_banner",