Module cm 

Core Media types and wrappers

This module provides Rust wrappers for Core Media framework types used in screen capture operations.

Main Types

• CMSampleBuffer - Container for media samples (audio/video frames)
• CMTime - Time value with rational timescale for precise timing
• IOSurface - Hardware-accelerated surface for zero-copy GPU access
• CMBlockBuffer - Block of contiguous data (audio/compressed video)
• AudioBuffer - Audio data buffer with sample data
• AudioBufferList - Collection of audio buffers for multi-channel audio
• SCFrameStatus - Status of a captured frame (complete, idle, dropped, etc.)

Example

use screencapturekit::cm::{CMSampleBuffer, CMSampleBufferExt, CMSampleBufferSCExt, CMTime, SCFrameStatus};

fn process_frame(sample: CMSampleBuffer) {
    // Check frame status (SCStream-specific attachment).
    if sample.frame_status() == Some(SCFrameStatus::Complete) {
        // Get timestamp.
        let pts = sample.presentation_timestamp();
        println!("Frame at {:?}", pts);

        // Access pixel buffer for CPU processing.
        if let Some(pixel_buffer) = sample.image_buffer() {
            // Access IOSurface for GPU processing.
            if let Some(surface) = pixel_buffer.io_surface() {
                println!("Surface: {}x{}", surface.width(), surface.height());
            }
        }
    }
}

Modules

codec_types

Common codec type constants

ffi

Raw FFI bindings for Core Media types.

iosurface

IOSurface — re-exported from apple-cf so all doom-fish crates share one canonical IOSurface type.

media_types

Common media type constants

Structs

AudioBuffer

Raw audio buffer containing sample data

AudioBufferList

List of audio buffers from an audio sample

AudioBufferListIter

Iterator over audio buffers in an AudioBufferList

AudioBufferListRaw

List of audio buffers from an audio sample

AudioBufferRef

Reference to an audio buffer with convenience methods

CMBlockBuffer

Block buffer containing contiguous media data

CMClock

CMClock wrapper for synchronization clock

CMFormatDescription

Owned wrapper around CMFormatDescriptionRef.

CMSampleBuffer

Re-exported CMSampleBuffer — same opaque-pointer wrapper used across the doom-fish suite. Owned reference to a CoreMedia CMSampleBufferRef.

CMSampleTimingInfo

Sample timing information

CMTime

CMTime representation matching Core Media’s CMTime

FrameInfo

Snapshot of every SCStreamFrameInfo attachment on a sample buffer.

IOSurface

Hardware-accelerated surface for efficient frame delivery

IOSurfaceLockGuard

RAII guard for locked IOSurface

IOSurfaceLockOptions

Lock options for IOSurface

PlaneProperties

Properties for a single plane in a multi-planar IOSurface

Enums

SCFrameStatus

Frame status for captured screen content

Traits

CMSampleBufferDataBufferExt

Convenience: like apple_cf::cm::CMSampleBuffer::data_buffer but returns the local crate::cm::CMBlockBuffer (which is currently a different wrapper around the same underlying type).

CMSampleBufferExt

Extension trait carrying generic CMSampleBuffer accessors that aren’t available on apple_cf::cm::CMSampleBuffer yet (planned for an apple-cf v0.2 release).

CMSampleBufferSCExt

Extension trait that exposes SCStreamFrameInfo attachment accessors on any CMSampleBuffer produced by ScreenCaptureKit.