Image Upscaling

Upscale an image using Topaz Image Upscaler via fal.ai async queue.

Ask the user for:

• IMAGE_URL: public URL of the image to upscale
• SCALE (optional): upscale factor — 2 (default), 4
• OUTPUT_FILE (optional): path to save the result (default: ~/Downloads/upscaled_[timestamp].jpg)

Then run the following steps:

Step 1 — Check API key:

if [ -z "$FAL_KEY" ]; then
  echo "ERROR: FAL_KEY not set."
  echo "Run /pocket-knife:setup to configure your API keys."
  exit 1
fi

Step 2 — Submit upscaling job:

IMAGE_URL="[USER_IMAGE_URL_HERE]"
SCALE="${SCALE:-2}"
OUTPUT_FILE="${OUTPUT_FILE:-$HOME/Downloads/upscaled_$(date +%s).jpg}"
MODEL_ID="fal-ai/topaz/upscale/image"
MAX_WAIT=180
POLL_INTERVAL=5

SUBMIT_RESPONSE=$(curl --fail-with-body -s \
  -X POST "https://queue.fal.run/${MODEL_ID}" \
  -H "Authorization: Key $FAL_KEY" \
  -H "Content-Type: application/json" \
  -d "{\"image_url\": \"$IMAGE_URL\", \"scale\": $SCALE}" \
  2>&1)

EXIT_CODE=$?
if [ $EXIT_CODE -ne 0 ]; then
  if echo "$SUBMIT_RESPONSE" | grep -qi "401\|unauthorized"; then
    echo "ERROR: Invalid FAL_KEY. Check your key in ~/.claude/.env"
  else
    echo "ERROR: fal.ai job submission failed (code $EXIT_CODE)."
    echo "$SUBMIT_RESPONSE"
  fi
  exit 1
fi

REQUEST_ID=$(echo "$SUBMIT_RESPONSE" | python3 -c "
import sys, json