Papers › Compression with Flows via Local Bits-Back Coding

Compression with Flows via Local Bits-Back Coding

21 May 2019NeurIPS 2019 12arXiv:1905.08500archive 2025-07-28

Jonathan Ho, Evan Lohn, Pieter Abbeel

Likelihood-based generative models are the backbones of lossless compression due to the guaranteed existence of codes with lengths close to negative log likelihood. However, there is no guaranteed existence of computationally efficient codes that achieve these lengths, and coding algorithms must be hand-tailored to specific types of generative models to ensure computational efficiency. Such coding algorithms are known for autoregressive models and variational autoencoders, but not for general types of flow models. To fill in this gap, we introduce local bits-back coding, a new compression technique for flow models. We present efficient algorithms that instantiate our technique for many popular types of flows, and we demonstrate that our algorithms closely achieve theoretical codelengths for state-of-the-art flow models on high-dimensional data.

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compute_jacobian hojonathanho/localbitsback/compression/blackbox.py official repository unverified MIT (permissive) · 6546340b60a0db0c · report
concat_elu hojonathanho/localbitsback/compression/coupling.py official repository unverified MIT (permissive) · 9953b28b1527a27e · report
depth_to_space hojonathanho/localbitsback/compression/coupling.py official repository unverified MIT (permissive) · 321263f39df39cc3 · report
inverse_sigmoid hojonathanho/localbitsback/compression/utils.py official repository unverified MIT (permissive) · 755efb24f63a5a6c · report
is_real_type hojonathanho/localbitsback/compression/bitstream.py official repository unverified MIT (permissive) · f9c0f60f522ef8e1 · report
is_sym_type hojonathanho/localbitsback/compression/bitstream.py official repository unverified MIT (permissive) · 32885bb81a6183b6 · report
logistic_logcdf hojonathanho/localbitsback/compression/logistic.py official repository unverified MIT (permissive) · 1b3f475609fa4f7f · report
logistic_logpdf hojonathanho/localbitsback/compression/logistic.py official repository unverified MIT (permissive) · 92a39c6cf1325433 · report
mixlogistic_logpdf hojonathanho/localbitsback/compression/logistic.py official repository unverified MIT (permissive) · 28f4d43740cbfafd · report
space_to_depth hojonathanho/localbitsback/compression/coupling.py official repository unverified MIT (permissive) · 33514ec7c72a14ac · report
standard_normal_logp hojonathanho/localbitsback/compression/utils.py official repository unverified MIT (permissive) · 07e7946c0986886e · report
sumflat hojonathanho/localbitsback/compression/utils.py official repository unverified MIT (permissive) · 66218714ad7612c3 · report

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