Papers › Photorealistic Text-to-Image Diffusion Models with Deep Language Understanding

Photorealistic Text-to-Image Diffusion Models with Deep Language Understanding

23 May 2022arXiv:2205.11487archive 2025-07-28

Chitwan Saharia, William Chan, Saurabh Saxena, Lala Li, Jay Whang, Emily Denton, Seyed Kamyar Seyed Ghasemipour, Burcu Karagol Ayan, S. Sara Mahdavi, Rapha Gontijo Lopes, Tim Salimans, Jonathan Ho, David J Fleet, Mohammad Norouzi

We present Imagen, a text-to-image diffusion model with an unprecedented degree of photorealism and a deep level of language understanding. Imagen builds on the power of large transformer language models in understanding text and hinges on the strength of diffusion models in high-fidelity image generation. Our key discovery is that generic large language models (e.g. T5), pretrained on text-only corpora, are surprisingly effective at encoding text for image synthesis: increasing the size of the language model in Imagen boosts both sample fidelity and image-text alignment much more than increasing the size of the image diffusion model. Imagen achieves a new state-of-the-art FID score of 7.27 on the COCO dataset, without ever training on COCO, and human raters find Imagen samples to be on par with the COCO data itself in image-text alignment. To assess text-to-image models in greater depth, we introduce DrawBench, a comprehensive and challenging benchmark for text-to-image models. With DrawBench, we compare Imagen with recent methods including VQ-GAN+CLIP, Latent Diffusion Models, and DALL-E 2, and find that human raters prefer Imagen over other models in side-by-side comparisons, both in terms of sample quality and image-text alignment. See https://imagen.research.google/ for an overview of the results.

PaperPDFCodeCode Syntology ran

In Syntology Open this paper in Syntology's Atlas, the map of the papers in Syntology's graph and their citations.

For agents, Syntology's MCP tool lists every function and class Syntology harvested from this paper and whether it ran (how to connect): get_harvested_code_for_paper(arxiv_id="2205.11487")

Code

Syntology Ran 5 of 11 code samples harvested from 3 repositories linked to this paper; 6 have no recorded run. Of those that ran: 5 ran with no contract checked.

By repository: community (archive-listed): 11 samples from 3 repositories, 5 ran. The run record, sample by sample. “Ran” means executed on a synthesized input, not that the code is correct or reproduces the paper.

deep-floyd/if mentioned on GitHubpytorchNOASSERTION report
layer6ai-labs/direct-cms mentioned on GitHubpytorch report
teapearce/conditional_diffusion_mnist mentioned on GitHubpytorch report

Repository list and official/mentioned flags are the archive's, frozen 2025-07-28. Reachability, where shown, is from one Syntology probe window (2026-09-16 to 2026-09-18); repositories not probed show nothing. GitHub stars are not tracked.

Code Syntology ran Syntology

11 samples harvested; 5 ran; 0 honoured the contract we drafted; 6 have no recorded run. Read from Syntology's graph 2026-09-24; that is when this build read the record, not when the samples ran.

5ran
6unverified

Licence: 9 of the 11 samples are pointer only, meaning Syntology does not serve that copy's text. This page shows no code text for any sample; each one links to its file in the repository.

Harvested from 3 repositories linked to this paper, official or community; each sample names its own and says which. “Ran” means the sample executed on a synthesized input. It does not mean the output is correct, and nothing here reproduces the paper's results. “Honoured” and “violated” refer to a contract Syntology drafted from the code itself; “our draft was wrong” and “fixture could not drive it” are failures of Syntology's instrument, not of the code.

Each sample ends with its code_sha256, Syntology's identity for that exact code. An agent fetches the stored sample with Syntology's MCP tool get_code(code_sha256="…") (how to connect); click an identity to copy that call.

Repository labels, per sample. official repository: The archive marks this repository official for the paper. named in the paper: The archive records that the paper mentions this repository; it is not marked official. community (archive-listed): In the archive's code links for this paper, not marked official and not recorded as mentioned in the paper. found in paper text by Syntology: Syntology found this repository in the paper's own text; whether it is the authors' implementation is not asserted. community: Not in the archive's code links for this paper; a community repository Syntology harvested. Samples from a repository marked official are listed first. Licence labels name the repository's licence as recorded at harvest. “Pointer only” means Syntology does not serve that copy's text, for one of four reasons: no licence file was found; the licence was not identified; the licence is recorded as permissive but that copy's record is not marked cleared; or the licence is outside the permissive list Syntology serves text under (MIT, Apache-2.0, BSD and similar). Some licences outside that list permit redistribution, such as WTFPL, and GPL-3.0 under its conditions; they are simply not on the list. Hover a licence label for the reason. File links open the file on GitHub at the default branch, which may have changed since the harvest.

AttentionPooling deep-floyd/if/deepfloyd_if/model/unet.py community (archive-listed) ran licence not identified · pointer only · 572c310ea05bf309 · report
Downsample deep-floyd/if/deepfloyd_if/model/unet.py community (archive-listed) ran fingerprinted licence not identified · pointer only · 93058e5e24fa4d4a · report
QKVAttention deep-floyd/if/deepfloyd_if/model/unet.py community (archive-listed) ran licence not identified · pointer only · c024083e30c5368d · report
UnetDown teapearce/conditional_diffusion_mnist/script.py community (archive-listed) ran · metamorphic tier: invariant fingerprinted MIT (permissive) · c1a53d10c7cfa17e · report
Upsample deep-floyd/if/deepfloyd_if/model/unet.py community (archive-listed) ran fingerprinted licence not identified · pointer only · 4f1ccffbc59c4bbe · report
AttentionBlock deep-floyd/if/deepfloyd_if/model/unet.py community (archive-listed) unverified licence not identified · pointer only · 83356f082da409f5 · report
ContextUnet teapearce/conditional_diffusion_mnist/script.py community (archive-listed) unverified MIT (permissive) · 156e412579f74583 · report
ResBlock deep-floyd/if/deepfloyd_if/model/unet.py community (archive-listed) unverified licence not identified · pointer only · 9878524ba095b65b · report
Text2ImUNet cene555/Imagen-pytorch/imagen_pytorch/text2im_model.py community (archive-listed) unverified no licence file found · pointer only · 7fcd4eb74a12867c · report
TimestepEmbedSequential deep-floyd/if/deepfloyd_if/model/unet.py community (archive-listed) unverified licence not identified · pointer only · 79ba2446de89789e · report
UNetModel deep-floyd/if/deepfloyd_if/model/unet.py community (archive-listed) unverified licence not identified · pointer only · c27dfab7177fdf2b · report

Datasets

Introduced by this paper, per the archive.

DrawBench

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Text-to-Image Generation COCO (Common Objects in Context) Imagen (zero-shot) FID 7.27 #15 of 69 Archive leaderboard report

Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.

Methods

Diffusion

Report a problem or propose a change · a person checks every report against the paper or source before anything changes; decisions are listed on /corrections