<?xml version="1.0" encoding="utf-8" standalone="yes"?><rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>SAM | Yufei Liu's Homepages</title><link>https://liu-yufei.github.io/tags/sam/</link><atom:link href="https://liu-yufei.github.io/tags/sam/index.xml" rel="self" type="application/rss+xml"/><description>SAM</description><generator>Hugo Blox Builder (https://hugoblox.com)</generator><language>en-us</language><lastBuildDate>Tue, 01 Sep 2026 00:00:00 +0000</lastBuildDate><image><url>https://liu-yufei.github.io/media/icon_hu17033853472409137288.png</url><title>SAM</title><link>https://liu-yufei.github.io/tags/sam/</link></image><item><title>SynPo: Boosting Training-Free Few-Shot Medical Segmentation via High-Quality Negative Prompts</title><link>https://liu-yufei.github.io/publication/synpo/</link><pubDate>Tue, 01 Sep 2026 00:00:00 +0000</pubDate><guid>https://liu-yufei.github.io/publication/synpo/</guid><description>&lt;p>SynPo addresses weak negative prompts in training-free few-shot medical image segmentation. It combines SAM and DINOv2 features to construct a synergistic confidence map, then selects informative positive and negative points through confidence-aware sampling and clustering.&lt;/p>
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&lt;section class="synpo-results" aria-labelledby="synpo-results-title">
&lt;header class="synpo-results__header">
&lt;h2 id="synpo-results-title">SynPo&lt;/h2>
&lt;p>Training-free few-shot medical segmentation with confidence-map synergy and informative negative prompts&lt;/p>
&lt;/header>
&lt;div class="synpo-results__layout">
&lt;div class="synpo-results__main">
&lt;div class="synpo-results__scroll" role="region" aria-label="Segmentation benchmark results" tabindex="0">
&lt;table>
&lt;thead>
&lt;tr>
&lt;th rowspan="2">Method&lt;/th>
&lt;th colspan="5">CHAOS-MRI&lt;/th>
&lt;th colspan="5">Synapse-CT&lt;/th>
&lt;/tr>
&lt;tr>
&lt;th>Spleen&lt;/th>&lt;th>Liver&lt;/th>&lt;th>LK&lt;/th>&lt;th>RK&lt;/th>&lt;th>Mean&lt;/th>
&lt;th>Spleen&lt;/th>&lt;th>Liver&lt;/th>&lt;th>LK&lt;/th>&lt;th>RK&lt;/th>&lt;th>Mean&lt;/th>
&lt;/tr>
&lt;/thead>
&lt;tbody>
&lt;tr>&lt;td>SSL-ALPNet&lt;span class="synpo-results__setting">trained&lt;/span>&lt;/td>&lt;td>67.02&lt;/td>&lt;td>73.05&lt;/td>&lt;td>73.63&lt;/td>&lt;td>78.39&lt;/td>&lt;td>73.02&lt;/td>&lt;td>60.25&lt;/td>&lt;td>73.65&lt;/td>&lt;td>63.34&lt;/td>&lt;td>54.82&lt;/td>&lt;td>63.02&lt;/td>&lt;/tr>
&lt;tr>&lt;td>ADNet&lt;span class="synpo-results__setting">trained&lt;/span>&lt;/td>&lt;td>75.92&lt;/td>&lt;td>80.81&lt;/td>&lt;td>75.28&lt;/td>&lt;td>83.28&lt;/td>&lt;td>78.82&lt;/td>&lt;td>63.48&lt;/td>&lt;td>77.24&lt;/td>&lt;td>72.13&lt;/td>&lt;td>79.06&lt;/td>&lt;td>72.97&lt;/td>&lt;/tr>
&lt;tr>&lt;td>Q-Net&lt;span class="synpo-results__setting">trained&lt;/span>&lt;/td>&lt;td>75.99&lt;/td>&lt;td>81.74&lt;/td>&lt;td>78.36&lt;/td>&lt;td>87.98&lt;/td>&lt;td>81.02&lt;/td>&lt;td>74.86&lt;/td>&lt;td>71.21&lt;/td>&lt;td>75.26&lt;/td>&lt;td>74.79&lt;/td>&lt;td>74.03&lt;/td>&lt;/tr>
&lt;tr>&lt;td>RPT&lt;span class="synpo-results__setting">trained&lt;/span>&lt;/td>&lt;td>76.37&lt;/td>&lt;td>82.86&lt;/td>&lt;td>80.72&lt;/td>&lt;td>89.82&lt;/td>&lt;td>82.44&lt;/td>&lt;td>79.13&lt;/td>&lt;td>82.57&lt;/td>&lt;td>77.05&lt;/td>&lt;td>72.58&lt;/td>&lt;td>77.83&lt;/td>&lt;/tr>
&lt;tr>&lt;td>GMRD&lt;span class="synpo-results__setting">trained&lt;/span>&lt;/td>&lt;td>76.09&lt;/td>&lt;td>81.42&lt;/td>&lt;td>83.96&lt;/td>&lt;td>90.12&lt;/td>&lt;td>82.90&lt;/td>&lt;td>78.31&lt;/td>&lt;td>79.60&lt;/td>&lt;td>81.70&lt;/td>&lt;td>74.46&lt;/td>&lt;td>78.52&lt;/td>&lt;/tr>
&lt;tr class="divider">&lt;td>PerSAM&lt;span class="synpo-results__setting">training-free&lt;/span>&lt;/td>&lt;td>69.14&lt;/td>&lt;td>42.44&lt;/td>&lt;td>64.84&lt;/td>&lt;td>71.36&lt;/td>&lt;td>61.12&lt;/td>&lt;td>65.03&lt;/td>&lt;td>65.55&lt;/td>&lt;td>58.47&lt;/td>&lt;td>60.31&lt;/td>&lt;td>62.34&lt;/td>&lt;/tr>
&lt;tr>&lt;td>ProtoSAM&lt;span class="synpo-results__setting">training-free&lt;/span>&lt;/td>&lt;td>76.51&lt;/td>&lt;td>81.94&lt;/td>&lt;td>71.46&lt;/td>&lt;td>81.43&lt;/td>&lt;td>77.83&lt;/td>&lt;td>65.50&lt;/td>&lt;td>87.84&lt;/td>&lt;td>69.44&lt;/td>&lt;td>71.04&lt;/td>&lt;td>73.45&lt;/td>&lt;/tr>
&lt;tr class="synpo-row">&lt;td>SynPo (ours)&lt;span class="synpo-results__setting">training-free&lt;/span>&lt;/td>&lt;td>80.30&lt;/td>&lt;td>77.32&lt;/td>&lt;td>77.32&lt;/td>&lt;td>83.04&lt;/td>&lt;td>79.50&lt;/td>&lt;td>83.76&lt;/td>&lt;td>81.32&lt;/td>&lt;td>75.00&lt;/td>&lt;td>79.63&lt;/td>&lt;td>79.91&lt;/td>&lt;/tr>
&lt;/tbody>
&lt;/table>
&lt;/div>
&lt;img class="synpo-results__qualitative" src="qualitative-results.png" alt="Qualitative abdominal organ segmentation results across four anatomical targets">
&lt;p class="synpo-results__caption">Qualitative results on abdominal MRI. Colored overlays show the predicted organ masks.&lt;/p>
&lt;/div>
&lt;aside class="synpo-results__side" aria-label="Ablation studies">
&lt;section>
&lt;h3>Module ablation&lt;/h3>
&lt;div class="synpo-results__scroll">
&lt;table>
&lt;thead>&lt;tr>&lt;th>SAM&lt;/th>&lt;th>DINO&lt;/th>&lt;th>PSM&lt;/th>&lt;th>NRM&lt;/th>&lt;th>Dice&lt;/th>&lt;th>Gain&lt;/th>&lt;/tr>&lt;/thead>
&lt;tbody>
&lt;tr>&lt;td>✓&lt;/td>&lt;td>&lt;/td>&lt;td>&lt;/td>&lt;td>&lt;/td>&lt;td>57.48&lt;/td>&lt;td>–&lt;/td>&lt;/tr>
&lt;tr>&lt;td>✓&lt;/td>&lt;td>✓&lt;/td>&lt;td>&lt;/td>&lt;td>&lt;/td>&lt;td>66.70&lt;/td>&lt;td class="gain">+9.22&lt;/td>&lt;/tr>
&lt;tr>&lt;td>✓&lt;/td>&lt;td>✓&lt;/td>&lt;td>✓&lt;/td>&lt;td>&lt;/td>&lt;td>78.74&lt;/td>&lt;td class="gain">+12.04&lt;/td>&lt;/tr>
&lt;tr>&lt;td>✓&lt;/td>&lt;td>✓&lt;/td>&lt;td>✓&lt;/td>&lt;td>✓&lt;/td>&lt;td class="best">79.93&lt;/td>&lt;td class="gain">+1.19&lt;/td>&lt;/tr>
&lt;/tbody>
&lt;/table>
&lt;/div>
&lt;/section>
&lt;section>
&lt;h3>Negative-prompt strategy on CHAOS&lt;/h3>
&lt;div class="synpo-results__scroll">
&lt;table>
&lt;thead>&lt;tr>&lt;th>Model&lt;/th>&lt;th>Dice&lt;/th>&lt;/tr>&lt;/thead>
&lt;tbody>
&lt;tr>&lt;td>PerSAM&lt;/td>&lt;td>56.72&lt;/td>&lt;/tr>
&lt;tr>&lt;td>+ Negative Point Selection&lt;/td>&lt;td class="best">68.90&lt;/td>&lt;/tr>
&lt;/tbody>
&lt;/table>
&lt;/div>
&lt;/section>
&lt;p class="synpo-results__takeaway">SynPo achieves a mean Dice score of &lt;strong>79.91&lt;/strong> on Synapse-CT without task-specific training. The module study shows the largest gain comes from the Point Selection Module.&lt;/p>
&lt;/aside>
&lt;/div>
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