Imaging, DSP & Coding¶
Bitstream arithmetic shines when the output quality metric is perceptual (PSNR / SSIM) or algorithmic (BER after iterations), not bit-exact equality.
Imaging & DSP¶
Classic SC case studies encode pixels or filter coefficients as densities, then implement:
- Local thresholding and morphological-style ops
- FIR-like filtering with scaled MUX adds
- Edge / texture features where small density errors vanish after quantization to display bits
graph LR
Img[Pixels] --> SNG[SNG / B2S]
SNG --> Kern[SC kernel: AND / MUX / counter]
Kern --> Dec[Decode / binary out]
Dec --> Metric[PSNR ยท SSIM ยท task score]
Design tip: compare energy at iso-PSNR (or iso-task), not iso-\(N\). A longer stream that wastes energy is not a win.
Coding & communications¶
Iterative soft decoders (LDPC, turbo-like BP, MIMO detection) already pass messages that are probabilities. Mapping those messages to stochastic wires can shrink check-node / variable-node logic, especially in fully parallel layouts.
Challenges unique to this domain:
| Issue | Why it matters |
|---|---|
| BER cliffs | Small message bias can raise error floors |
| Throughput | Frame latency vs stream length \(N\) |
| Mixed signal / CIM | New MS-SCIM style datapaths need careful SNR budgeting |
Shared lesson across both bridges¶
Applications succeed when designers treat SC as a noise channel with a known model, then allocate \(N\), parallelism, and hybrid binary stages the way a communications engineer allocates SNR.
Continue with taxonomies:
๐ DOI starting points¶
- Stochastic Phansalkar thresholding architecture: DOI 10.1109/TVLSI.2023.3348809
- Parallel stochastic multiplier for signal processing: DOI 10.1109/TVLSI.2026.3722919
- Fully parallel stochastic LDPC decoder: DOI 10.1109/TVLSI.2024.3488716
- Stochastic BP iterative detection & decoding: DOI 10.1109/TVLSI.2024.3477963