Skip to content
tezvyn:

All bites

The whole library, newest first. Filter by what you are here for, or pick a topic if you already know.

8668 bites

Page 60

Computer Vision2 min read

Designing a baseline Visual Question Answering model

Encode the image with a CNN, encode the question with an RNN or embedding, fuse the two vectors, and classify over a fixed answer vocabulary.

Computer Vision2 min read

Semantic, instance, and panoptic segmentation

Semantic labels every pixel by class without separating objects; instance separates individual objects but may skip background; panoptic unifies both, labeling stuff and distinct thing instances.

Computer Vision2 min read

Designing a high-resolution photorealistic face generator

Weigh StyleGAN's fast, controllable style-based synthesis against diffusion's diversity and stable training; handle scale via progressive or multi-resolution synthesis; protect diversity to avoid mode…

Computer Vision2 min read

DDPM versus DDIM sampling trade-offs

DDPM is a stochastic Markov chain needing many steps; DDIM is a non-Markovian, deterministic sampler that skips steps for far faster inference and reproducible, invertible latents, trading a…

Computer Vision2 min read

Classifier-free guidance in diffusion models

Train one model jointly on conditional and dropped-condition inputs; at inference extrapolate from unconditional toward conditional prediction via a guidance scale, sharpening prompt adherence…

Computer Vision2 min read

Unpaired image translation with CycleGAN

CycleGAN uses two generators and two discriminators with a cycle-consistency loss that forces translating to the other domain and back to reconstruct the input, removing the need for paired data.

Computer Vision2 min read

How text prompts guide Stable Diffusion

A frozen text encoder turns the prompt into token embeddings, which feed the U-Net via cross-attention at each denoising step so the prompt steers generation; classifier-free guidance amplifies the…

Computer Vision1 min read

Why U-Net skip connections matter for denoising

Skips carry high-resolution spatial detail from encoder to decoder, preserving fine structure lost in downsampling and easing gradient flow, which lets the model restore detail while removing…

Computer Vision2 min read

Evaluating generative models with FID versus IS

FID compares Inception feature distributions of real and fake images via Frechet distance between two Gaussians; it uses real data as reference and detects diversity issues, unlike IS which uses no real…

Computer Vision2 min read

Mode collapse in GAN training

Generator produces few outputs ignoring data diversity, caused by chasing whatever fools the current discriminator; mitigate with minibatch discrimination, unrolled GANs, or Wasserstein loss.

Computer Vision2 min read

Diffusion forward and reverse processes

Forward process gradually adds Gaussian noise until data is pure noise; reverse process learns to denoise step by step; the network predicts the noise added at each timestep.

Computer Vision1 min read

GAN architecture: generator and discriminator roles

Generator maps noise to fake samples, discriminator classifies real versus fake, they train as a two-player game until samples fool the discriminator.

Computer Vision2 min read

Attention in diffusion U-Nets for text conditioning

Self-attention mixes spatial features at low-res blocks; cross-attention has image queries attend to text-token keys/values; placed inside transformer blocks.

Computer Vision2 min read

Pure ViT vs hybrid CNN-Transformer for medical segmentation

Pure ViT captures global context but is data hungry and weak on local detail; hybrid CNN-Transformer gets local features cheaply plus global attention, ideal for scarce…

Computer Vision2 min read

Core principles of a Neural Radiance Field

An MLP maps a 3D point plus view direction to color and density; novel views render by casting rays, sampling points, querying the MLP, and volume-integrating along each ray.

Computer Vision2 min read

Why ViTs need positional embeddings

Self-attention is permutation invariant so patch order is lost; positional embeddings restore spatial location. CNNs encode position implicitly via the fixed convolution grid.

Computer Vision1 min read

Cross-attention for visual question answering

In cross-attention queries come from one modality and keys/values from the other, e.g. text queries attend over image features so the question selects relevant regions.

Computer Vision2 min read

How Swin Transformer achieves linear attention

Swin computes attention within local non-overlapping windows of fixed size, making cost linear in patches, then shifts windows between layers so information crosses boundaries.

Computer Vision1 min read

Inductive biases of ViT versus CNN

CNNs bake in locality and translation equivariance; a plain ViT has almost none beyond patch structure, so it must learn spatial relations from data, needing large datasets or strong pretraining.

Computer Vision1 min read

Self-attention over image patches explained

Each patch projects to query, key, value; a patch's query is scored against all keys, softmax-normalized into weights, used to combine all values.