Table of Contents

Enum H264AMFLevel

Namespace
VisioForge.Core.Types.FFMPEGEXE
Assembly
VisioForge.Core.dll

Represents H.264 level constraints for the AMD AMF hardware encoder.

public enum H264AMFLevel

Fields

Auto = 0

Automatic level selection based on video parameters.

The encoder automatically selects the minimum level that supports:

  • Current resolution and frame rate
  • Configured bitrate and buffer size
  • Number of reference frames

This is the recommended setting unless specific device compatibility is required. The encoder will choose the most compatible level that doesn't unnecessarily restrict quality.

FFMPEG: -level 0 (or omit the parameter)

Level_1_0 = 10

Level 1.0 - Mobile phone video (176x144 @ 15fps).

Designed for basic mobile phones and low-bandwidth applications:

  • Max resolution: 176x144 (QCIF)
  • Max frame rate: 15 fps
  • Max bitrate: 64 kbps
  • Max reference frames: 4

Use cases:

  • Video calls on 3G networks
  • MMS video messages
  • Extremely low bandwidth streaming

FFMPEG: -level 1.0

Level_1_1 = 11

Level 1.1 - Enhanced mobile video (352x288 @ 7.5fps).

Supports CIF resolution for better mobile video:

  • Max resolution: 352x288 (CIF) or 320x240
  • Max frame rate: 7.5-15 fps depending on resolution
  • Max bitrate: 192 kbps
  • Typical: 176x144 @ 30fps or 320x240 @ 10fps

Use cases:

  • Basic video conferencing
  • Mobile streaming on older devices
  • Low-quality security cameras

FFMPEG: -level 1.1

Level_1_2 = 12

Level 1.2 - CIF video at full frame rate (352x288 @ 15fps).

Standard definition for mobile and web video:

  • Max resolution: 352x288 (CIF)
  • Max frame rate: 15-30 fps
  • Max bitrate: 384 kbps
  • Supports: 320x240 @ 20fps, 352x288 @ 15fps

Common uses:

  • Mobile video playback
  • Web video conferencing
  • Portable media players

FFMPEG: -level 1.2

Level_1_3 = 13

Level 1.3 - Higher quality CIF (352x288 @ 30fps).

Full frame rate CIF for smooth motion:

  • Max resolution: 352x288 (CIF)
  • Max frame rate: 30 fps
  • Max bitrate: 768 kbps
  • Reference frames: Up to 4

Ideal for:

  • Smooth motion mobile video
  • Video podcasts
  • E-learning content

FFMPEG: -level 1.3

Level_2_0 = 20

Level 2.0 - SD video support (352x480 @ 30fps).

Supports standard definition resolutions:

  • Max resolution: 352x576 (576i), 352x480 (480i)
  • Max frame rate: 30 fps (or 25 fps for PAL)
  • Max bitrate: 2 Mbps
  • Typical: 352x288 @ 30fps with higher quality

Applications:

  • DVD-quality web video
  • Standard definition broadcasts
  • Portable device playback

FFMPEG: -level 2.0

Level_2_1 = 21

Level 2.1 - Improved SD video (352x576 @ 25fps).

Enhanced standard definition with better motion:

  • Max resolution: 352x576 (PAL) or 480x480
  • Max frame rate: 25-30 fps
  • Max bitrate: 4 Mbps
  • Supports: 480x360 @ 30fps, 640x360 @ 15fps

Common for:

  • Widescreen web video
  • Mobile device recording
  • Video messaging apps

FFMPEG: -level 2.1

Level_2_2 = 22

Level 2.2 - Full SD support (720x480 @ 15fps).

Full SD resolution support:

  • Max resolution: 720x576 (PAL) or 720x480 (NTSC)
  • Max frame rate: 15 fps at max resolution
  • Max bitrate: 4 Mbps
  • Supports: 640x480 @ 15fps, 480x360 @ 30fps

Use cases:

  • SD video editing
  • Legacy content conversion
  • Low-bandwidth HD alternatives

FFMPEG: -level 2.2

Level_3_0 = 30

Level 3.0 - Entry-level HD (720x480 @ 30fps).

Supports full SD and entry-level HD:

  • Max resolution: 720x576 @ 25fps or 720x480 @ 30fps
  • Max bitrate: 10 Mbps
  • Max reference frames: 5
  • DPB size: 6 frames

Standard for:

  • DVD video encoding
  • Standard web video
  • Set-top box compatibility
  • Mobile HD video

FFMPEG: -level 3.0

Level_3_1 = 31

Level 3.1 - HD Ready (1280x720 @ 30fps).

Standard HD 720p support:

  • Max resolution: 1280x720 (720p)
  • Max frame rate: 30 fps
  • Max bitrate: 14 Mbps
  • Reference frames: Up to 5

Most common for:

  • HD web streaming (YouTube, Vimeo)
  • HD video conferencing
  • Game console video playback
  • Entry-level Blu-ray

This is the minimum level for true HD content.

FFMPEG: -level 3.1

Level_3_2 = 32

Level 3.2 - HD Ready Plus (1280x720 @ 60fps).

High frame rate 720p support:

  • Max resolution: 1280x1024 or 1280x720 @ 60fps
  • Max bitrate: 20 Mbps
  • Supports smooth motion HD

Applications:

  • Sports broadcasting at 720p60
  • High frame rate gaming content
  • Action cameras (720p60)
  • Smooth motion web video

FFMPEG: -level 3.2

Level_4_0 = 40

Level 4.0 - Full HD (1920x1080 @ 30fps).

Standard Full HD 1080p support:

  • Max resolution: 1920x1080 (1080p) or 2048x1024
  • Max frame rate: 30 fps (or 25 fps for PAL)
  • Max bitrate: 20 Mbps
  • Reference frames: Up to 4

Industry standard for:

  • HD television broadcasts
  • Blu-ray disc (with level 4.1)
  • Premium web video
  • Digital cinema
  • Professional video production

FFMPEG: -level 4.0

Level_4_1 = 41

Level 4.1 - Full HD Plus (1920x1080 @ 30fps high bitrate).

Enhanced Full HD with higher bitrate:

  • Max resolution: 1920x1080 (1080p) or 2048x1088
  • Max frame rate: 30 fps
  • Max bitrate: 50 Mbps
  • Reference frames: Up to 4

Required for:

  • Blu-ray disc authoring
  • High-quality streaming services
  • Professional video delivery
  • Broadcast contribution feeds

Most TVs and devices support up to level 4.1.

FFMPEG: -level 4.1

Level_4_2 = 42

Level 4.2 - Full HD 60fps (1920x1080 @ 60fps).

High frame rate Full HD:

  • Max resolution: 1920x1080 @ 60fps or 2048x1088 @ 60fps
  • Max bitrate: 50 Mbps
  • Supports 1080p60 for smooth motion

Use cases:

  • Sports broadcasts in 1080p60
  • Gaming content at 60fps
  • High-end video conferencing
  • Premium streaming services

Note: Not all devices support 1080p60 playback.

FFMPEG: -level 4.2

Level_5_0 = 50

Level 5.0 - 4K entry level (3840x2160 @ 30fps).

Basic 4K/UHD support:

  • Max resolution: 3840x2160 (4K) or 4096x2048
  • Max frame rate: 30 fps
  • Max bitrate: 135 Mbps
  • Higher macroblock processing rate

Applications:

  • 4K streaming services
  • Ultra HD Blu-ray
  • Digital cinema (2K scope)
  • Professional 4K production

Requires HEVC for practical bitrates.

FFMPEG: -level 5.0

Level_5_1 = 51

Level 5.1 - 4K standard (4096x2160 @ 30fps).

Full 4K cinema support:

  • Max resolution: 4096x2160 (Cinema 4K)
  • Max frame rate: 30 fps
  • Max bitrate: 240 Mbps
  • Professional cinema applications

Used for:

  • Digital cinema distribution
  • High-end 4K production
  • Professional archival
  • Premium 4K streaming

FFMPEG: -level 5.1

Level_5_2 = 52

Level 5.2 - 4K high frame rate (4096x2160 @ 60fps).

High frame rate 4K:

  • Max resolution: 4096x2160 @ 60fps
  • Max bitrate: 240 Mbps
  • Supports smooth motion 4K

Applications:

  • High-end sports broadcasting
  • Premium gaming content
  • Future-proof content creation
  • VR/360 video at high quality

Limited device support.

FFMPEG: -level 5.2

Level_6_0 = 60

Level 6.0 - 8K support (7680x4320 @ 30fps).

Ultra-high resolution support:

  • Max resolution: 7680x4320 (8K UHD)
  • Max frame rate: 30 fps
  • Max bitrate: 240 Mbps
  • Extreme processing requirements

Future applications:

  • 8K television broadcasts
  • Ultra-high resolution displays
  • Professional production
  • Digital signage

Very limited support in current hardware.

FFMPEG: -level 6.0

Level_6_1 = 61

Level 6.1 - 8K enhanced (7680x4320 @ 60fps).

High frame rate 8K:

  • Max resolution: 7680x4320 @ 60fps
  • Max bitrate: 480 Mbps
  • Theoretical maximum for H.264

Experimental uses:

  • Research and development
  • Future broadcast standards
  • Specialized applications

Not practical with current technology.

FFMPEG: -level 6.1

Level_6_2 = 62

Level 6.2 - Maximum level (7680x4320 @ 120fps).

Theoretical maximum for H.264:

  • Max resolution: 7680x4320 @ 120fps
  • Max bitrate: 800 Mbps
  • Beyond current hardware capabilities

Reserved for:

  • Future applications
  • Specification completeness
  • Extreme high-end production

No practical use cases currently.

FFMPEG: -level 6.2

Remarks

H.264 levels define limits on decoder complexity by constraining parameters like:

  • Maximum resolution and frame rate
  • Maximum bitrate and buffer size
  • Number of reference frames
  • Maximum macroblock processing rate

Each level is designed for specific device capabilities, from mobile phones to 4K televisions. The AMD AMF encoder enforces these constraints when a specific level is selected, ensuring compatibility with target devices.

Level selection affects:

  • Playback device compatibility
  • Maximum achievable quality
  • Streaming protocol compliance (HLS, DASH)
  • Hardware decoder requirements

FFMPEG usage: -c:v h264_amf -level [1.0|1.1|...|6.2]