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Pika post-trained MiniMax H3 to generate video with synchronized audio in six sampling steps instead of 50, and released the generator adapters and inference code with open weights

AspireAI community · Pika
Pika released H3 Flex, a post-trained MiniMax H3 that generates video with synchronized stereo audio in six denoising steps rather than the base model's 50, and shipped the generator adapters and inference code as open weights. At launch Pika said Flex ranked first among open-weights models and seventh overall on DesignArena's text-to-video board, accepts up to 12 reference files, and can produce a 15-second 768p clip in as little as seven seconds of transformer computation. The hosted API adds 1080p, 2K and 4K finishing plus five separate audio stems, but local open-weight inference stops at native 480p and 768p. Pika's own footnote notes the seven-second figure measures transformer computation for a 15-second clip rather than end-to-end API latency, so real generation time depends on hardware, references and service overhead.
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