Add measured Galaxy S26 NPU/GPU encoder rows

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  1. README.md +16 -0
README.md CHANGED
@@ -209,6 +209,22 @@ model reproduces the f32 token sequence exactly on the dense test window on
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  both Apple devices, and its transcripts are identical between the M4 Max
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  and the Pi 5 on all 12 test clips.
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  ### Accuracy note
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  In a 12-clip spot check (LibriSpeech dev-clean samples plus two
 
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  both Apple devices, and its transcripts are identical between the M4 Max
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  and the Pi 5 on all 12 test clips.
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+ ### Snapdragon NPU / GPU β€” Galaxy S26
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+ Measured on a physical Samsung Galaxy S26 (SM-S942Q, Snapdragon 8 Elite Gen 5 / SM8850, Hexagon v81, Android 16) with LiteRT `CompiledModel` 2.2.0 β€” 5 warm-up runs then 50 timed runs, one accelerator per process, every row at device thermal status `NONE`, delegate placement confirmed from logcat per row. The figures are the **`encode` signature only** (the model's first signature, which the API's default `run()` executes β€” the encoder over the raw 80,000-sample / 5 s waveform input); not comparable to the end-to-end window totals in the CPU table above. NPU in HTP BURST mode, on-device (JIT) compilation.
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+ | File | Compute unit | Encode (median / min) | Load |
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+ |---|---|---|---|
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+ | `moonshine_tiny_5s_f32.tflite` | **GPU (Adreno)** | **5.4 ms** / 5.4 ms | 1.7 s |
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+ | `moonshine_tiny_5s_i8.tflite` | NPU (Hexagon, JIT) β€” first launch | 1294 ms / 1281 ms | 13.1 s |
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+ | `moonshine_tiny_5s_i8.tflite` | NPU (Hexagon, JIT) β€” cached | 1264 ms / 1247 ms | 0.37 s |
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+ What the table says:
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+ - **On this device the GPU running the f32 file is the only fast accelerated path**: 5.4 ms for the 5 s window's encoder, encoder-only RTF 0.001.
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+ - **The Hexagon runs the i8 encoder in ~1.26 s** β€” slower than the Pi 5's CPU in the table above. The two accelerators also refuse each other's file: f32 compiles for the NPU but fails at output-buffer creation, and i8 fails to compile on the GPU. So there is no NPU recommendation to make from this run.
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+ - `moonshine_tiny_5s_f32_Qualcomm_SM8850.tflite` (the embedded precompiled context) failed to invoke on both accelerators in this harness and is not quoted.
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  ### Accuracy note
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  In a 12-clip spot check (LibriSpeech dev-clean samples plus two