1 files changed, 53 insertions, 0 deletions
diff --git a/scripts/capture-screen.sh b/scripts/capture-screen.sh
new file mode 100755
index 0000000..40bb860
--- /dev/null
+++ b/scripts/capture-screen.sh
@@ -0,0 +1,53 @@
+#!/usr/bin/env bash
+# Captures the screen and writes a JPEG to standard output.
+#
+#   scripts/capture-screen.sh [width] [output]
+#
+#   width   Width to scale the capture down to. Defaults to 1280, the
+#           measured minimum for the model to read UI text without making
+#           it up (see docs/RENDIMIENTO.md).
+#   output  A specific monitor. Empty = everything there is.
+#
+# It lives outside the binary so supporting a new graphical environment means
+# editing this script, not recompiling. Detection goes from most specific to
+# most general.
+set -euo pipefail
+
+WIDTH="${1:-1280}"
+OUTPUT="${2:-}"
+
+missing() { echo "nothing to capture the screen with: $1" >&2; exit 1; }
+
+# Scaling happens here and not in the binary: shrinking before sending the
+# image to the model is what brings the cost from 23 s down to 7 s, and ffmpeg
+# is already needed for the camera.
+shrink() {
+  if command -v ffmpeg >/dev/null 2>&1; then
+    ffmpeg -hide_banner -loglevel error -i - \
+           -vf "scale=${WIDTH}:-2:flags=lanczos" -q:v 3 -f image2 -c:v mjpeg -
+  else
+    cat   # without ffmpeg it goes full size: slow, but it works
+  fi
+}
+
+if [ -n "${WAYLAND_DISPLAY:-}" ] && command -v grim >/dev/null 2>&1; then
+  # wlroots: Hyprland, Sway, river… grim writes to stdout with «-».
+  if [ -n "$OUTPUT" ]; then
+    grim -t png -o "$OUTPUT" - | shrink
+  else
+    grim -t png - | shrink
+  fi
+elif [ -n "${WAYLAND_DISPLAY:-}" ] && command -v spectacle >/dev/null 2>&1; then
+  TMP=$(mktemp --suffix=.png); trap 'rm -f "$TMP"' EXIT
+  spectacle -b -n -f -o "$TMP" >/dev/null 2>&1
+  shrink < "$TMP"
+elif [ -n "${DISPLAY:-}" ] && command -v maim >/dev/null 2>&1; then
+  maim --format=png /dev/stdout | shrink
+elif [ -n "${DISPLAY:-}" ] && command -v import >/dev/null 2>&1; then
+  # ImageMagick, present on almost any X11.
+  import -silent -window root png:- | shrink
+elif [ -n "${DISPLAY:-}" ] && command -v scrot >/dev/null 2>&1; then
+  scrot -o /dev/stdout | shrink
+else
+  missing "install grim (Wayland) or maim/imagemagick (X11)"
+fi