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特征图上的地址、通道与感受野","sha256":"3c9d3d137b1c9f52c46828c2478bea8703c205e06204f45d3da6c3ea1f2dba96","chapter":{"id":"II","title":"区域、像素与实例"},"unit":{"id":"spatial-answer-contract","title":"任务究竟要求留下什么信息？"},"page":{"id":"reading-opening","title":"特征图上的地址、通道与感受野","number":1},"sectionTitle":"特征图上的地址、通道与感受野","currentQuestion":"特征图上的地址、通道与感受野","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"previousBlock":null,"nextBlock":"b-d8e1b6dfbc7470207babdcc1","prerequisites":[{"id":"b-d8e1b6dfbc7470207babdcc1","url":"#b-d8e1b6dfbc7470207babdcc1","role":"problem-context"}],"relatedBlocks":[{"id":"b-808af4f5c131214d87b5635e","url":"#b-808af4f5c131214d87b5635e","relation":"figure-and-explanation"}]},{"id":"b-d8e1b6dfbc7470207babdcc1","type":"p","scope":"spatial-feature-address","url":"https://codingai-lec03.pages.dev/course/blocks/spatial-feature-address.html#b-d8e1b6dfbc7470207babdcc1","content":"把特征图读成“空间地址＋通道向量”。步长不是感受野，通道也不是预先指定的类别；池化前是否保留网格，是把分类表示迁到空间任务时的关键接口选择。与 P44 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C 维向量 $F[:,u,v]$。网格索引保留“从哪里读”，通道则保存学到的多种响应。某个通道可能对边缘、纹理或更复杂组合敏感，但我们通常没有事先把第 17 通道指定为“杯子”。","sha256":"e236d07c03fd0aa86f0395a9a54ba4e25b4ef97bd11f3b3e9ef9155e502b5c75","chapter":{"id":"II","title":"区域、像素与实例"},"unit":{"id":"spatial-answer-contract","title":"任务究竟要求留下什么信息？"},"page":{"id":"reading-opening","title":"特征图上的地址、通道与感受野","number":1},"sectionTitle":"特征图上的地址、通道与感受野","currentQuestion":"特征图上的地址、通道与感受野","sourceSlides":[],"knowledgeBlock":null,"formulas":[{"latex":"F\\in\\mathbb R^{C\\times H'\\times 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更大的区域影响。图上画一个格子对应杯沿，只是在标读取位置，不能理解成这个向量只看了那一个小方块。","sha256":"ecf5f72cc15fce79a32242c02527bd9e01fab6fc94fc6777906263521919a7d8","chapter":{"id":"II","title":"区域、像素与实例"},"unit":{"id":"spatial-answer-contract","title":"任务究竟要求留下什么信息？"},"page":{"id":"reading-opening","title":"特征图上的地址、通道与感受野","number":1},"sectionTitle":"特征图上的地址、通道与感受野","currentQuestion":"特征图上的地址、通道与感受野","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"previousBlock":"b-9751d13729b201de0fbac52c","nextBlock":"b-81e12d26520e6288fb0b9396","prerequisites":[{"id":"b-0331bfb7d72e2518472e826d","url":"#b-0331bfb7d72e2518472e826d","role":"section-title"},{"id":"b-d8e1b6dfbc7470207babdcc1","url":"#b-d8e1b6dfbc7470207babdcc1","role":"problem-context"}],"relatedBlocks":[{"id":"b-808af4f5c131214d87b5635e","url":"#b-808af4f5c131214d87b5635e","relation":"figure-and-explanation"}]},{"id":"b-81e12d26520e6288fb0b9396","type":"p","scope":"spatial-feature-address","url":"https://codingai-lec03.pages.dev/course/blocks/spatial-feature-address.html#b-81e12d26520e6288fb0b9396","content":"全局平均池化沿空间求均值，使分类头方便读取整图统计；若任务要定位，我们常在池化前读取网格。也不能只凭“一个向量”断言全部位置必丢：通道可能编码位置统计。P44 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03 课堂图解 P26；图像中的位置；空间特征 F；保留网格 → 定位 / 像素；全局汇总 → 整图向量；空间位置与通道共同承载信息；示意格值不对应某个训练模型的激活。\n\n同一空间特征既可保留网格，也可被汇总为整图向量。 查看对应图解状态\n\n- 图像中的位置\n- 空间特征 F\n- 保留网格 → 定位 / 像素\n- 全局汇总 → 整图向量\n- 空间位置与通道共同承载信息；示意格值不对应某个训练模型的激活。同一空间特征既可保留网格，也可被汇总为整图向量。 [查看对应图解状态](/#/l3-r2-p26/0)[查看完整图解](/#/l3-r2-p26/0)","sha256":"787eed0b7e1d98f172ddce55c48c532938d6165d37571987b33a428445f95721","chapter":{"id":"II","title":"区域、像素与实例"},"unit":{"id":"spatial-answer-contract","title":"任务究竟要求留下什么信息？"},"page":{"id":"reading-opening","title":"特征图上的地址、通道与感受野","number":1},"sectionTitle":"特征图上的地址、通道与感受野","currentQuestion":"特征图上的地址、通道与感受野","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"figure":{"caption":"同一空间特征既可保留网格，也可被汇总为整图向量。 查看对应图解状态","labels":["图像中的位置","空间特征 F","保留网格 → 定位 / 像素","全局汇总 → 整图向量","空间位置与通道共同承载信息；示意格值不对应某个训练模型的激活。"],"description":"同一空间特征既可保留网格，也可被汇总为整图向量。 查看对应图解状态图像中的位置空间特征 F保留网格 → 定位 / 像素全局汇总 → 整图向量空间位置与通道共同承载信息；示意格值不对应某个训练模型的激活。","evidenceIdentity":"同一空间特征既可保留网格，也可被汇总为整图向量。 查看对应图解状态","images":[{"src":"/assets/display/8ced939a1fd55047fbf73ea5.webp","alt":""}]},"previousBlock":"b-4b1031ead0c0b05530ccf175","nextBlock":"b-b7fbbee626643ea9ce5e811b","prerequisites":[{"id":"b-0331bfb7d72e2518472e826d","url":"#b-0331bfb7d72e2518472e826d","role":"section-title"},{"id":"b-d8e1b6dfbc7470207babdcc1","url":"#b-d8e1b6dfbc7470207babdcc1","role":"problem-context"}],"relatedBlocks":[]},{"id":"b-b7fbbee626643ea9ce5e811b","type":"h2","scope":"spatial-feature-address","url":"https://codingai-lec03.pages.dev/course/blocks/spatial-feature-address.html#b-b7fbbee626643ea9ce5e811b","content":"## 继续阅读与实验","sha256":"2b9ccef7e1220e2250cceff1abd8bdd736b42f8da5a223f26b029f44b962e807","chapter":{"id":"II","title":"区域、像素与实例"},"unit":{"id":"spatial-answer-contract","title":"任务究竟要求留下什么信息？"},"page":{"id":"reading-opening","title":"特征图上的地址、通道与感受野","number":1},"sectionTitle":"特征图上的地址、通道与感受野","currentQuestion":"特征图上的地址、通道与感受野","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"previousBlock":"b-808af4f5c131214d87b5635e","nextBlock":null,"prerequisites":[{"id":"b-0331bfb7d72e2518472e826d","url":"#b-0331bfb7d72e2518472e826d","role":"section-title"},{"id":"b-d8e1b6dfbc7470207babdcc1","url":"#b-d8e1b6dfbc7470207babdcc1","role":"problem-context"}],"relatedBlocks":[{"id":"b-808af4f5c131214d87b5635e","url":"#b-808af4f5c131214d87b5635e","relation":"figure-and-explanation"}]}]}