Struct BitstreamStats 

pub struct BitstreamStats { /* private fields */ }

Accumulated bitstream quality statistics.

Call BitstreamStats::update_psnr and/or BitstreamStats::update_ssim after each encoded frame to accumulate per-frame metrics. Aggregated averages can then be retrieved via BitstreamStats::mean_psnr and BitstreamStats::mean_ssim.

Implementations

impl BitstreamStats

pub fn new() -> Self

Create a new, empty statistics accumulator.

pub fn update_psnr(&mut self, orig: &[u8], recon: &[u8], w: u32, h: u32)

Compute and record the PSNR between the original and reconstructed pixel buffers for one frame.

PSNR is computed on the luma (Y) plane:

MSE = sum((orig[i] - recon[i])^2) / (w * h)
PSNR = 10 * log10(255^2 / MSE)

An MSE of 0.0 (identical buffers) yields +∞ dB; in that case 100.0 dB is recorded as a practical maximum.

Parameters

• orig – original uncompressed pixel buffer (u8 luma, length w * h).
• recon – reconstructed pixel buffer (same layout as orig).
• w – frame width in pixels.
• h – frame height in pixels.

Panics

Panics if orig.len() != w * h or recon.len() != w * h.

pub fn mean_psnr(&self) -> Option<f64>

Returns the mean PSNR across all recorded frames, or None if no frames have been processed.

pub fn min_psnr(&self) -> Option<f64>

Returns the minimum per-frame PSNR, or None if no frames recorded.

pub fn max_psnr(&self) -> Option<f64>

Returns the maximum per-frame PSNR, or None if no frames recorded.

pub fn update_ssim(&mut self, orig: &[u8], recon: &[u8], w: u32, h: u32)

Compute and record the mean SSIM between original and reconstructed buffers for one frame.

Uses the simplified single-window SSIM formula (per-image, not per-patch) as a fast approximation:

μ_x, μ_y  — mean pixel values
σ_x, σ_y  — standard deviations
σ_xy      — cross-covariance
SSIM = (2μ_xμ_y + C1)(2σ_xy + C2) / ((μ_x²+μ_y²+C1)(σ_x²+σ_y²+C2))

with C1 = (0.01 * 255)^2 and C2 = (0.03 * 255)^2.

Parameters

• orig – original pixel buffer (u8 luma, length w * h).
• recon – reconstructed pixel buffer (same layout).
• w – frame width in pixels.
• h – frame height in pixels.

Panics

Panics if orig.len() != w * h or recon.len() != w * h.

pub fn mean_ssim(&self) -> Option<f64>

Returns the mean SSIM across all recorded frames, or None if no frames have been processed.

pub fn min_ssim(&self) -> Option<f64>

Returns the minimum per-frame SSIM, or None if no frames recorded.

pub fn max_ssim(&self) -> Option<f64>

Returns the maximum per-frame SSIM, or None if no frames recorded.

pub fn psnr_frame_count(&self) -> u64

Returns the number of frames that contributed to PSNR statistics.

pub fn ssim_frame_count(&self) -> u64

Returns the number of frames that contributed to SSIM statistics.

pub fn reset(&mut self)

Reset all statistics.

Trait Implementations

impl Clone for BitstreamStats

fn clone(&self) -> BitstreamStats

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for BitstreamStats

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for BitstreamStats

fn default() -> BitstreamStats

Returns the “default value” for a type.