Improve ffmpeg versions handling (#16712)

* Improve ffmpeg versions handling

* Remove fallback from LIBAVFORMAT_VERSION_MAJOR, it should always be set

* Mention ffprobe in custom ffmpeg docs

* Fix ffmpeg extraction

* Fix go2rtc example formatting

* Add fallback back to LIBAVFORMAT_VERSION_MAJOR

* Fix linter

docker/main/rootfs/etc/s6-overlay/s6-rc.d/frigate/run

@@ -43,8 +43,10 @@ function migrate_db_path() {
 }
 
 function set_libva_version() {
-    local ffmpeg_path=$(python3 /usr/local/ffmpeg/get_ffmpeg_path.py)
-    export LIBAVFORMAT_VERSION_MAJOR=$($ffmpeg_path -version | grep -Po "libavformat\W+\K\d+")
+    local ffmpeg_path
+    ffmpeg_path=$(python3 /usr/local/ffmpeg/get_ffmpeg_path.py)
+    LIBAVFORMAT_VERSION_MAJOR=$("$ffmpeg_path" -version | grep -Po "libavformat\W+\K\d+")
+    export LIBAVFORMAT_VERSION_MAJOR
 }
 
 echo "[INFO] Preparing Frigate..."

docker/main/rootfs/etc/s6-overlay/s6-rc.d/go2rtc/run

@@ -44,10 +44,14 @@ function get_ip_and_port_from_supervisor() {
 }
 
 function set_libva_version() {
-    local ffmpeg_path=$(python3 /usr/local/ffmpeg/get_ffmpeg_path.py)
-    export LIBAVFORMAT_VERSION_MAJOR=$($ffmpeg_path -version | grep -Po "libavformat\W+\K\d+")
+    local ffmpeg_path
+    ffmpeg_path=$(python3 /usr/local/ffmpeg/get_ffmpeg_path.py)
+    LIBAVFORMAT_VERSION_MAJOR=$("$ffmpeg_path" -version | grep -Po "libavformat\W+\K\d+")
+    export LIBAVFORMAT_VERSION_MAJOR
 }
 
+set_libva_version
+
 if [[ -f "/dev/shm/go2rtc.yaml" ]]; then
     echo "[INFO] Removing stale config from last run..."
     rm /dev/shm/go2rtc.yaml
@@ -66,8 +70,6 @@ else
     echo "[WARNING] Unable to remove existing go2rtc config. Changes made to your frigate config file may not be recognized. Please remove the /dev/shm/go2rtc.yaml from your docker host manually."
 fi
 
-set_libva_version
-
 readonly config_path="/config"
 
 if [[ -x "${config_path}/go2rtc" ]]; then

docker/main/rootfs/usr/local/ffmpeg/get_ffmpeg_path.py

@@ -1,6 +1,5 @@
 import json
 import os
-import shutil
 import sys
 
 from ruamel.yaml import YAML
@@ -35,10 +34,7 @@ except FileNotFoundError:
 
 path = config.get("ffmpeg", {}).get("path", "default")
 if path == "default":
-    if shutil.which("ffmpeg") is None:
-        print(f"/usr/lib/ffmpeg/{DEFAULT_FFMPEG_VERSION}/bin/ffmpeg")
-    else:
-        print("ffmpeg")
+    print(f"/usr/lib/ffmpeg/{DEFAULT_FFMPEG_VERSION}/bin/ffmpeg")
 elif path in INCLUDED_FFMPEG_VERSIONS:
     print(f"/usr/lib/ffmpeg/{path}/bin/ffmpeg")
 else:

docker/main/rootfs/usr/local/go2rtc/create_config.py

@@ -2,7 +2,6 @@
 
 import json
 import os
-import shutil
 import sys
 from pathlib import Path
 
@@ -13,6 +12,7 @@ from frigate.const import (
     BIRDSEYE_PIPE,
     DEFAULT_FFMPEG_VERSION,
     INCLUDED_FFMPEG_VERSIONS,
+    LIBAVFORMAT_VERSION_MAJOR,
 )
 from frigate.ffmpeg_presets import parse_preset_hardware_acceleration_encode
 
@@ -115,10 +115,7 @@ else:
 # ensure ffmpeg path is set correctly
 path = config.get("ffmpeg", {}).get("path", "default")
 if path == "default":
-    if shutil.which("ffmpeg") is None:
-        ffmpeg_path = f"/usr/lib/ffmpeg/{DEFAULT_FFMPEG_VERSION}/bin/ffmpeg"
-    else:
-        ffmpeg_path = "ffmpeg"
+    ffmpeg_path = f"/usr/lib/ffmpeg/{DEFAULT_FFMPEG_VERSION}/bin/ffmpeg"
 elif path in INCLUDED_FFMPEG_VERSIONS:
     ffmpeg_path = f"/usr/lib/ffmpeg/{path}/bin/ffmpeg"
 else:
@@ -130,14 +127,12 @@ elif go2rtc_config["ffmpeg"].get("bin") is None:
     go2rtc_config["ffmpeg"]["bin"] = ffmpeg_path
 
 # need to replace ffmpeg command when using ffmpeg4
-if int(os.environ.get("LIBAVFORMAT_VERSION_MAJOR", "59") or "59") < 59:
-    if go2rtc_config["ffmpeg"].get("rtsp") is None:
-        go2rtc_config["ffmpeg"]["rtsp"] = (
-            "-fflags nobuffer -flags low_delay -stimeout 5000000 -user_agent go2rtc/ffmpeg -rtsp_transport tcp -i {input}"
-        )
-else:
+if LIBAVFORMAT_VERSION_MAJOR < 59:
+    rtsp_args = "-fflags nobuffer -flags low_delay -stimeout 5000000 -user_agent go2rtc/ffmpeg -rtsp_transport tcp -i {input}"
     if go2rtc_config.get("ffmpeg") is None:
-        go2rtc_config["ffmpeg"] = {"path": ""}
+        go2rtc_config["ffmpeg"] = {"rtsp": rtsp_args}
+    elif go2rtc_config["ffmpeg"].get("rtsp") is None:
+        go2rtc_config["ffmpeg"]["rtsp"] = rtsp_args
 
 for name in go2rtc_config.get("streams", {}):
     stream = go2rtc_config["streams"][name]