yt_thumb.sh

yt_thumb.sh

#!/bin/bash

# Usage: ./yt_thumb.sh VIDEO_ID [WIDTH] [OUTPUT_FILE]
# Example: ./yt_thumb.sh hcx0SSvk7zg 480 thumbnail.jpg

VIDEO_ID="$1"
WIDTH="${2:-}"
OUTPUT="${3:-yt_thumb_${VIDEO_ID}.jpg}"

if [ -z "$VIDEO_ID" ]; then
    echo "Usage: $0 VIDEO_ID [WIDTH] [OUTPUT_FILE]"
    echo "Example: $0 hcx0SSvk7zg 480 thumbnail.jpg"
    exit 1
fi

TEMP_DIR=$(mktemp -d)
THUMB="$TEMP_DIR/thumb.jpg"
PLAY_BTN="$TEMP_DIR/play.png"

# Download YouTube thumbnail
echo "Downloading thumbnail..."
curl -s -o "$THUMB" "https://img.youtube.com/vi/${VIDEO_ID}/maxresdefault.jpg"

if [ ! -s "$THUMB" ]; then
    echo "Failed to download thumbnail. Trying hqdefault..."
    curl -s -o "$THUMB" "https://img.youtube.com/vi/${VIDEO_ID}/hqdefault.jpg"
fi

if [ ! -s "$THUMB" ]; then
    echo "Error: Could not download thumbnail for video ID: $VIDEO_ID"
    rm -rf "$TEMP_DIR"
    exit 1
fi

# Resize thumbnail if WIDTH is specified
if [ -n "$WIDTH" ]; then
    echo "Resizing thumbnail to width ${WIDTH}..."
    RESIZED="$TEMP_DIR/resized.jpg"
    ffmpeg -y -loglevel error \
        -i "$THUMB" \
        -vf "scale=${WIDTH}:-1" \
        "$RESIZED"
    mv "$RESIZED" "$THUMB"
fi

# Create anti-aliased play button (4x size then downscale)
echo "Creating play button..."
ffmpeg -y -loglevel error \
    -f lavfi -i "color=black@0.0:s=400x400,format=rgba" \
    -vf "geq=\
r='if(lt(pow(X-200,2)+pow(Y-200,2),32400)*gte(X,140)*lte(X,280)*gte(Y,120+(X-140)*0.57)*lte(Y,280-(X-140)*0.57),255,0)':\
g='if(lt(pow(X-200,2)+pow(Y-200,2),32400)*gte(X,140)*lte(X,280)*gte(Y,120+(X-140)*0.57)*lte(Y,280-(X-140)*0.57),255,0)':\
b='if(lt(pow(X-200,2)+pow(Y-200,2),32400)*gte(X,140)*lte(X,280)*gte(Y,120+(X-140)*0.57)*lte(Y,280-(X-140)*0.57),255,0)':\
a='if(lt(pow(X-200,2)+pow(Y-200,2),32400),180,0)',\
scale=100:100:flags=lanczos" \
    -frames:v 1 -update 1 "$PLAY_BTN"

# Overlay play button on thumbnail
echo "Creating final image..."
ffmpeg -y -loglevel error \
    -i "$THUMB" -i "$PLAY_BTN" \
    -filter_complex "[0:v][1:v]overlay=(W-w)/2:(H-h)/2" \
    "$OUTPUT"

# Cleanup
rm -rf "$TEMP_DIR"

echo "Done: $OUTPUT"