Support for kernel module settings via the V4L2LOOPBACK_DC_PARAMS

environment variable

The user is prompted for the desired video resolution on startup.

linuxdeploy-plugin-droidcam.sh

@@ -50,12 +50,18 @@ EOF
 chmod +x "$appdir"/usr/bin/zenity-askpass
 cat > "$appdir"/usr/bin/droidcam-module-load <<\EOF
 #!/bin/sh
+set -e
 if [ "$(id -u)" -ne 0 ]
 then
     echo "Needs to be run as root." >&2
     exit 1
 fi
+V4L2LOOPBACK_DC_PARAMS="${V4L2LOOPBACK_DC_PARAMS:-width=640 height=480}"
 LOWER_DIR="$1"
+if [ -n "$2" ]
+then
+    V4L2LOOPBACK_DC_PARAMS="$2"
+fi
 if ! modinfo v4l2loopback-dc >/dev/null 2>&1
 then
     TMP_DIR="$(mktemp -d -p /tmp appimage-droidcam.XXXXXX)"
@@ -71,15 +77,68 @@ then
     mount -t overlay -o lowerdir="$LOWER_DIR":"/usr/lib/modules/$(uname -r)",upperdir="$TMP_DIR/upper",workdir="$TMP_DIR/work" overlay "/usr/lib/modules/$(uname -r)"
     depmod
 fi
+if lsmod | grep -q '^v4l2loopback_dc\b'
+then
+    if ! modprobe -r v4l2loopback-dc
+    then
+        rmmod -f v4l2loopback-dc
+    fi
+fi
 modprobe videodev
-modprobe -f v4l2loopback-dc width=640 height=480
+modprobe -f v4l2loopback-dc $V4L2LOOPBACK_DC_PARAMS
 modprobe snd-aloop
 EOF
 chmod +x "$appdir"/usr/bin/droidcam-module-load
 mkdir -p "$appdir"/apprun-hooks
 cat > "$appdir"/apprun-hooks/linuxdeploy-plugin-droidcam.sh <<\EOF
 export PATH="$APPDIR/usr/bin:$PATH"
-if ! lsmod | grep -q '^v4l2loopback_dc\b'
+if command -v zenity >/dev/null
+then
+    has_zenity=1
+else
+    has_zenity=0
+fi
+if [ -z "$V4L2LOOPBACK_DC_PARAMS" ] && [ "$has_zenity" -eq 1 ]
+then
+    curr_width="640"
+    curr_height="480"
+    if [ -f /sys/module/v4l2loopback_dc/parameters/width ]
+    then
+        curr_width="$(cat /sys/module/v4l2loopback_dc/parameters/width)"
+    fi
+    if [ -f /sys/module/v4l2loopback_dc/parameters/height ]
+    then
+        curr_height="$(cat /sys/module/v4l2loopback_dc/parameters/height)"
+    fi
+    if res="$(printf '640x480\n800x600\n1024x576\n1280x720\n1920x1080\n' | zenity \
+        --list \
+        --title="DroidCam Resolution" \
+        --width=300 \
+        --height=300 \
+        --text="Resolution to use for the webcam.\nCurrent size is ${curr_width}x${curr_height}.\nDefault is 640x480.\nV4L2LOOPBACK_DC_PARAMS environment variable can be set with the parameters to pass to the module.\ne.g.: V4L2LOOPBACK_DC_PARAMS=\"width=640 height=480 video_nr=(-1|0..)\"" \
+        --column=Resolution)" && [ -n "$res" ]
+    then
+        V4L2LOOPBACK_DC_PARAMS="width=$(echo "$res" | cut -dx -f1) height=$(echo "$res" | cut -dx -f2)"
+        export V4L2LOOPBACK_DC_PARAMS
+    fi
+fi
+reload_module=0
+if [ -n "$V4L2LOOPBACK_DC_PARAMS" ]
+then
+    width="$(echo "$V4L2LOOPBACK_DC_PARAMS" | sed -n 's/^.*\bwidth=\([0-9]\+\).*$/\1/p')"
+    height="$(echo "$V4L2LOOPBACK_DC_PARAMS" | sed -n 's/^.*\bheight=\([0-9]\+\).*$/\1/p')"
+    video_nr="$(echo "$V4L2LOOPBACK_DC_PARAMS" | sed -n 's/^.*\bvideo_nr=\(-\?[0-9]\+\).*$/\1/p')"
+    if { [ -n "$width" ] && [ -f /sys/module/v4l2loopback_dc/parameters/width ] && \
+        [ "$width" != "$(cat /sys/module/v4l2loopback_dc/parameters/width)" ] ;} || \
+        { [ -n "$height" ] && [ -f /sys/module/v4l2loopback_dc/parameters/height ] && \
+        [ "$height" != "$(cat /sys/module/v4l2loopback_dc/parameters/height)" ] ;} || \
+        { [ -n "$video_nr" ] && [ -f /sys/module/v4l2loopback_dc/parameters/video_nr ] && \
+        [ "$video_nr" != "$(cat /sys/module/v4l2loopback_dc/parameters/video_nr)" ] ;}
+    then
+        reload_module=1
+    fi
+fi
+if [ "$reload_module" -eq 1 ] || ! lsmod | grep -q '^v4l2loopback_dc\b'
 then
     if [ -z "$SUDO_ASKPASS" ]
     then
@@ -96,12 +155,6 @@ then
             fi
         done
     fi
-    if command -v zenity >/dev/null
-    then
-        has_zenity=1
-    else
-        has_zenity=0
-    fi
     if [ ! -d "$APPDIR/usr/lib/modules/$(uname -r)" ]
     then
         if ! modinfo v4l2loopback_dc >/dev/null 2>&1
@@ -125,10 +178,12 @@ then
     if [ "$has_zenity" -eq 1 ]
     then
         mkfifo -m 600 "$TMP_DIR/progress"
-        cat "$TMP_DIR/progress" | zenity --progress --pulsate --no-cancel --auto-close --title="Installing kernel module" --width=300 --text="Installing kernel module" &
+        cat "$TMP_DIR/progress" | zenity --progress --pulsate --no-cancel --auto-close --title="DroidCam - Installing kernel module" --width=300 --text="Installing kernel module" &
         progress_pid="$!"
     fi
-    if ! cat "$APPDIR/usr/bin/droidcam-module-load" | sudo -A sh -s "$TMP_DIR/lower" 2>&1 | tee -a "$LOG_FILE" >&2
+    sudo_status="$TMP_DIR/sudo_status"
+    if ! cat "$APPDIR/usr/bin/droidcam-module-load" | { sudo -A sh -s "$TMP_DIR/lower" "$V4L2LOOPBACK_DC_PARAMS" 2>&1 || echo "$?" > "$sudo_status" ;} | tee -a "$LOG_FILE" >&2 || \
+        { [ -f "$sudo_status" ] && [ "$(cat "$sudo_status")" -ne 0 ] ;}
     then
         echo "ERROR! Failed to load the needed modules." 2>&1 | tee -a "$LOG_FILE" >&2
         zenity --error --width=300 --title="ERROR! Failed to load the needed modules." --text="$(cat "$LOG_FILE")" || true