Video Quality and Rendering

📹 Video Quality & Rendering

This guide covers all the options for controlling video output quality, resolution, encoding, and sharpness.

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Resolution Pipeline

Source Video → Download (--source-height) → Render (--render-height) → Final Output
   4K/2K/1080p       max / 1440 / 1080         source / 1440 / 1080

Source Download Height

Controls the maximum resolution downloaded from the source platform:

Value	Description
max (default)	Fetch the highest available quality
1080	Cap at 1080p
1440	Cap at 2K (1440p)
2160	Cap at 4K (2160p)

# Download highest quality available
python main.py --url "VIDEO_URL" --source-height max

# Cap at 1440p to save bandwidth
python main.py --url "VIDEO_URL" --source-height 1440

Render Output Height

Controls the final output video height:

Value	Description
1080 (default)	Standard HD output
1440	2K output
2160	4K output
source	Match the source video height

# Standard 1080p output
python main.py --url "VIDEO_URL" --render-height 1080

# Native 2K rendering
python main.py --url "VIDEO_URL" --source-height 1440 --render-height source

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Encoder Quality

CQ (NVENC — NVIDIA GPU Encoder)

Value	Quality	File Size
15-18	Ultra Sharp	Very Large
19-22	Sharp	Large
23 (default)	Standard	Balanced
24-28	Soft	Small
29-50	Blurry	Very Small

CRF (libx264 — CPU Encoder)

Value	Quality	File Size
15-17	Ultra Sharp	Very Large
18-19	Sharp	Large
20 (default)	Standard	Balanced
21-25	Soft	Small
26-50	Blurry	Very Small

# Ultra-sharp output
python main.py --url "VIDEO_URL" --video-cq 19 --video-crf 17

# Smaller files (lower quality)
python main.py --url "VIDEO_URL" --video-cq 28 --video-crf 25

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Encoder Preset

Controls the speed vs. quality tradeoff of the encoding process:

NVENC Presets (GPU)

p1 (fastest, lowest quality) → p7 (slowest, highest quality)

x264 Presets (CPU)

ultrafast → superfast → veryfast → faster → fast → medium → slow → slower → veryslow

# Slow encoding for maximum quality
python main.py --url "VIDEO_URL" --video-preset slow

# Fast encoding for quick preview
python main.py --url "VIDEO_URL" --video-preset veryfast

Use auto (default) to let the system choose the optimal preset.

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Bitrate

Value	Description
auto (default)	Resolution-aware: 4M (1080p), 8M (1440p), 12M (2K), 20M (4K)
8M	Fixed 8 Mbps
12M	Fixed 12 Mbps

# High bitrate for maximum quality
python main.py --url "VIDEO_URL" --video-bitrate 12M

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Sharpening

Apply a subtle sharpening filter for clearer output:

python main.py --url "VIDEO_URL" --video-sharpen

Best used in combination with high-resolution rendering:

# Ultra-HD 2K with sharpening
python main.py --url "VIDEO_URL" \
  --source-height 1440 \
  --render-height source \
  --video-sharpen

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Scaling Algorithm

Controls how the video is resized during rendering:

Algorithm	Description	Speed
lanczos (default)	Sharpest, preserves detail	Slowest
bicubic	Balanced quality	Medium
bilinear	Smooth but softer	Fast
area	Good for downscaling	Fast

python main.py --url "VIDEO_URL" --video-scale-algo lanczos

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Ambient Edge Glow

The engine can apply a dynamic ambient glow around the video edges (matching the video colors). By default, this is only active during the voice-over intro.

# Apply edge glow to the entire video
python main.py --url "VIDEO_URL" --edge-glow

Edge Glow Modes (--edge-glow-mode)

The underlying animation engine loops the glow effect. You can choose the rendering strategy:

Mode	Description	Tradeoffs
smooth (default)	Mathematically adjusts rotation speed for a seamless 10-second loop.	Perfectly smooth, no stutter at loop boundaries.
full	Renders the exact duration of the video (no looping needed).	Zero stutter, but computationally heavier for long clips.
default	Strict 10-second loop using the original speed.	May exhibit a slight visible stutter at the 10s mark.

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Quality Presets (Recipes)

Maximum Quality (Slow)

python main.py --url "VIDEO_URL" \
  --source-height 2160 \
  --render-height source \
  --video-cq 18 \
  --video-crf 16 \
  --video-preset slow \
  --video-scale-algo lanczos \
  --video-sharpen \
  --video-bitrate 20M

Standard Quality (Default)

python main.py --url "VIDEO_URL"
# Uses: source-height max, render-height 1080, cq 23, crf 20, lanczos

Fast Preview (Low Quality)

python main.py --url "VIDEO_URL" \
  --source-height 1080 \
  --video-cq 30 \
  --video-crf 28 \
  --video-preset veryfast \
  --video-scale-algo bilinear

TikTok/Reels Optimized

python main.py --url "VIDEO_URL" \
  --source-height 1440 \
  --render-height 1080 \
  --video-cq 21 \
  --video-crf 19 \
  --video-sharpen

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See Also

• CLI Reference — Full list of quality flags
• Google Colab Guide — Quality settings for cloud GPUs