{"version":2,"relationshipURLBase":"https://codingai-lec03.pages.dev/course/notebooks/2d81e2a1936043349eacb71c53c0defa.html","relationshipResolution":"Resolve relative relationship URLs against relationshipURLBase; complete records and absolute URLs are in blocks.","title":"CLS 08 · 密集预测、实例与集合输出","url":"https://codingai-lec03.pages.dev/course/notebooks/2d81e2a1936043349eacb71c53c0defa.html","markdown":"https://codingai-lec03.pages.dev/course/notebooks/2d81e2a1936043349eacb71c53c0defa.md","pages":[{"id":"reading-opening","title":"CLS 08 · 密集预测、实例与集合输出","unit":"怎样直接学习一张像素类别地图？","unitId":"pixel-prediction-objective","chapter":"II","number":1},{"id":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","title":"一张类别图怎样成为可训练的输出","unit":"怎样直接学习一张像素类别地图？","unitId":"pixel-prediction-objective","chapter":"II","number":2},{"id":"reading-block-8413a612fc314b05806c00e9cf00fb7a","title":"从类别像素走向逐个对象","unit":"怎样直接学习一张像素类别地图？","unitId":"pixel-prediction-objective","chapter":"II","number":3},{"id":"reading-block-59e4b23da62d4b709cc87f278811ec2f","title":"对齐的正面实证","unit":"怎样直接学习一张像素类别地图？","unitId":"pixel-prediction-objective","chapter":"II","number":4}],"aliases":[{"oldId":"b-f90d91771d065d713ea686fe","targetId":"b-f90d91771d065d713ea686fe","operation":"historical-explanation","sourceScope":"block-8413a612fc314b05806c00e9cf00fb7a"},{"oldId":"b-d5cbda44da5e67237970a16e","targetId":"b-d5cbda44da5e67237970a16e","operation":"historical-explanation","sourceScope":"block-8413a612fc314b05806c00e9cf00fb7a"},{"oldId":"b-89ef089484882b69157e4b33","targetId":"b-89ef089484882b69157e4b33","operation":"historical-explanation","sourceScope":"block-8413a612fc314b05806c00e9cf00fb7a"},{"oldId":"b-b5e0966ad99f143ebb1fff7c","targetId":"b-b5e0966ad99f143ebb1fff7c","operation":"historical-explanation","sourceScope":"block-8413a612fc314b05806c00e9cf00fb7a"},{"oldId":"b-777aa133f9d275d1ba9d0047","targetId":"b-777aa133f9d275d1ba9d0047","page":"reading-opening","operation":"move","beforeSHA256":"e4f817838c06f025f95e906deb158142e9364a9ad54a95e0fa2fdf2414eeb1d4","afterSHA256":"e4f817838c06f025f95e906deb158142e9364a9ad54a95e0fa2fdf2414eeb1d4","reason":"Same 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page"},{"oldId":"b-827fbf61e44d1405b6cd0486","targetId":"b-827fbf61e44d1405b6cd0486","page":"reading-opening","operation":"move","beforeSHA256":"f22152fd55dcdb0090b5653d37145694fd19388d31e10226549464fe8b483578","afterSHA256":"f22152fd55dcdb0090b5653d37145694fd19388d31e10226549464fe8b483578","reason":"Same source body in authored semantic page"},{"oldId":"b-d68c0fe4646a89db1c8a2d5a","targetId":"b-d68c0fe4646a89db1c8a2d5a","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"30ab9f304366670818536cf73c98c66aa814e8e31ecdbffcf19a4d6e7e7f22de","afterSHA256":"30ab9f304366670818536cf73c98c66aa814e8e31ecdbffcf19a4d6e7e7f22de","reason":"Same source body in authored semantic page"},{"oldId":"b-d76f1d331aa310461f13cdfc","targetId":"b-d76f1d331aa310461f13cdfc","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"72798cbfc37e71e8b9dbbcfe3cfb8a7b0fc2d74531b251cdcb3e0c9989b9c37d","afterSHA256":"72798cbfc37e71e8b9dbbcfe3cfb8a7b0fc2d74531b251cdcb3e0c9989b9c37d","reason":"Same source body in authored semantic page"},{"oldId":"b-21fe5755784d5232009cdd64","targetId":"b-21fe5755784d5232009cdd64","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"93743e4257248bf9219358b363aae08572036e7ccafb37b6917bd45eeacfbe96","afterSHA256":"93743e4257248bf9219358b363aae08572036e7ccafb37b6917bd45eeacfbe96","reason":"Same source body in authored semantic page"},{"oldId":"b-97a054a12812cb451ba3a866","targetId":"b-97a054a12812cb451ba3a866","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"ad5c18536ebaaed1683a9cbbc42e20e2f10a94f3ad582f81270f89de1719a98f","afterSHA256":"ad5c18536ebaaed1683a9cbbc42e20e2f10a94f3ad582f81270f89de1719a98f","reason":"Same source body in authored semantic page"},{"oldId":"b-794e274a9ee045ebec4c1393","targetId":"b-794e274a9ee045ebec4c1393","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"5409b0105bb5ec9dc3241c580e59c54772c6e8b9d8dbcfe5caf959343ea238a6","afterSHA256":"5409b0105bb5ec9dc3241c580e59c54772c6e8b9d8dbcfe5caf959343ea238a6","reason":"Same source body in authored semantic page"},{"oldId":"b-6d586f2f83d71b3286164507","targetId":"b-6d586f2f83d71b3286164507","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"77f6d53302f1be4d6d3ee57e02b21459f56e0aa208d6bbbd81accd9d8b377d53","afterSHA256":"77f6d53302f1be4d6d3ee57e02b21459f56e0aa208d6bbbd81accd9d8b377d53","reason":"Same source body in authored semantic page"},{"oldId":"b-8d743a2b44e6a2fe3d5b8d87","targetId":"b-8d743a2b44e6a2fe3d5b8d87","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"3e56a076a7b9a48f3f8c0e4a1ec3518b7589369f6099f713d3ab613354f864c0","afterSHA256":"3e56a076a7b9a48f3f8c0e4a1ec3518b7589369f6099f713d3ab613354f864c0","reason":"Same source body in authored semantic page"},{"oldId":"b-339fbb3f700976c14b19c7d3","targetId":"b-339fbb3f700976c14b19c7d3","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"ad790b051493beed5374493af79f9514dc8aa5e0b22af3b3dc4d840d31e23fe3","afterSHA256":"ad790b051493beed5374493af79f9514dc8aa5e0b22af3b3dc4d840d31e23fe3","reason":"Same source body in authored semantic page"},{"oldId":"b-eff5c5125472f1af4938f492","targetId":"b-eff5c5125472f1af4938f492","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"be0aaf3d04041ca7d223159fab6db6c9adaac7193b5a1788872d4d17ef5a188b","afterSHA256":"be0aaf3d04041ca7d223159fab6db6c9adaac7193b5a1788872d4d17ef5a188b","reason":"Same source body in authored semantic page"},{"oldId":"b-2a5c0cec0a018e2dd6852737","targetId":"b-2a5c0cec0a018e2dd6852737","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"a9149806afd622bccc16835a043e5f4608c2cf76dcabe0e7596a0cc5c2bf8c51","afterSHA256":"a9149806afd622bccc16835a043e5f4608c2cf76dcabe0e7596a0cc5c2bf8c51","reason":"Same source body in authored semantic page"},{"oldId":"b-97ef6b7e01b7ef46a283d525","targetId":"b-97ef6b7e01b7ef46a283d525","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"241bf275da03aa8d9391b79ee6cd44b57a829f6baa38512357bc65f453f808df","afterSHA256":"241bf275da03aa8d9391b79ee6cd44b57a829f6baa38512357bc65f453f808df","reason":"Same source body in authored semantic page"},{"oldId":"b-363c2eca1518150c2d0452eb","targetId":"b-363c2eca1518150c2d0452eb","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"cf7413ba356779e875fe91f4f34c7c315f7f7b7ce42e19b44ffd1dcb30d0d58b","afterSHA256":"cf7413ba356779e875fe91f4f34c7c315f7f7b7ce42e19b44ffd1dcb30d0d58b","reason":"Same source body in authored semantic page"},{"oldId":"b-764185f2da6bf4e9e96df5f8","targetId":"b-764185f2da6bf4e9e96df5f8","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"041babd888393a13f260ef325bcc31c4c9cd1e4f7df2491e324ddafb2b56cd23","afterSHA256":"041babd888393a13f260ef325bcc31c4c9cd1e4f7df2491e324ddafb2b56cd23","reason":"Same source body in authored semantic page"},{"oldId":"b-a3c063fe4b462a5dc1e1efa9","targetId":"b-a3c063fe4b462a5dc1e1efa9","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"c315ee35160727db2c7bb7bef724e45266800f78ea5d2880c7d3101479ad3b43","afterSHA256":"c315ee35160727db2c7bb7bef724e45266800f78ea5d2880c7d3101479ad3b43","reason":"Same source body in authored semantic page"},{"oldId":"b-837192084a99982d0b191a7c","targetId":"b-837192084a99982d0b191a7c","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"9d6d23d8e3c027ed4f0115e54b8a2a363b6e2f8a619951c7433c03f79bcd0992","afterSHA256":"9d6d23d8e3c027ed4f0115e54b8a2a363b6e2f8a619951c7433c03f79bcd0992","reason":"Same source body in authored semantic page"},{"oldId":"b-1796bd53636fa63536318135","targetId":"b-1796bd53636fa63536318135","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"ae393bf00717f2b8ab32d920a04af01319f2e21853fbca2d696f4bb48f770610","afterSHA256":"ae393bf00717f2b8ab32d920a04af01319f2e21853fbca2d696f4bb48f770610","reason":"Same source body in authored semantic page"},{"oldId":"b-e0452fd3ff72bbc299af051d","targetId":"b-e0452fd3ff72bbc299af051d","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"35d7aa5a6598e52321e9309a0916b06dc03cd25c5ad4df6383272b464361299a","afterSHA256":"35d7aa5a6598e52321e9309a0916b06dc03cd25c5ad4df6383272b464361299a","reason":"Same source body in authored semantic page"},{"oldId":"b-9fdfd157983bbeacbcf47651","targetId":"b-9fdfd157983bbeacbcf47651","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"cdf5e1ee80a89ea700fef3561ecdfa2d3713ae806370d2924e5897e2a5078529","afterSHA256":"cdf5e1ee80a89ea700fef3561ecdfa2d3713ae806370d2924e5897e2a5078529","reason":"Same source body in authored semantic page"},{"oldId":"b-38add6c70c6889e9b5bfe0fe","targetId":"b-38add6c70c6889e9b5bfe0fe","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"d8c17ff28b5b0d5b1671238ddcef7a1c477eeded2b48b525dadaddb86200d640","afterSHA256":"d8c17ff28b5b0d5b1671238ddcef7a1c477eeded2b48b525dadaddb86200d640","reason":"Same source body in authored semantic page"},{"oldId":"b-77e9bad6580adf72245b0b1b","targetId":"b-77e9bad6580adf72245b0b1b","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"13df4d569b221f8bc60c5de960a783d1972c800851f3e5ebd251ca5ca31bb27c","afterSHA256":"13df4d569b221f8bc60c5de960a783d1972c800851f3e5ebd251ca5ca31bb27c","reason":"Same source body in authored semantic page"},{"oldId":"b-77fa9f200f079dacc7a3a9c2","targetId":"b-77fa9f200f079dacc7a3a9c2","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"rewrite","beforeSHA256":"5530957dfc389313134c1ae2e8fbba7cb2ec21f5033903c548698fd1182a0ee5","afterSHA256":"d12b72281bce9d27865a10e904405cca1c2c915b9910c63934ad6f7d4439e49a","reason":"Same source identity with figure semantics or reading context enriched"},{"oldId":"b-5fca66dbeebb7c7f13b7429e","targetId":"b-5fca66dbeebb7c7f13b7429e","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"4c2978607bb7b437fdad1528eb065e99e5968fdc50592f9201ed43dcf3ded1a3","afterSHA256":"4c2978607bb7b437fdad1528eb065e99e5968fdc50592f9201ed43dcf3ded1a3","reason":"Same source body in authored semantic page"},{"oldId":"b-28d8109bbff9fb0b95b29853","targetId":"b-28d8109bbff9fb0b95b29853","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"939045e192e80393bc29ee5638c03a5341285cb4e18440f27403c32464cc6f54","afterSHA256":"939045e192e80393bc29ee5638c03a5341285cb4e18440f27403c32464cc6f54","reason":"Same source body in authored semantic page"},{"oldId":"b-ccd4d62ae8cc404c7d7fc519","targetId":"b-ccd4d62ae8cc404c7d7fc519","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"715899b38a78b3bf4f5526299aecfd4f7c5178ff28d2193adb58e1166be1ad9d","afterSHA256":"715899b38a78b3bf4f5526299aecfd4f7c5178ff28d2193adb58e1166be1ad9d","reason":"Same source body in authored semantic page"},{"oldId":"b-a7157bb26496b4a4704cd996","targetId":"b-a7157bb26496b4a4704cd996","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"rewrite","beforeSHA256":"1bdd695c84d8c10d3518a5f111bf260a1bf6eb69d2b1d291cf172813e2d66865","afterSHA256":"506f6e140199a9480864e32072bf7dc411386e1f8072f90aaf04d4a7616bf87e","reason":"Same source identity with figure semantics or reading context enriched"},{"oldId":"b-c53f468ae813334c225b18fa","targetId":"b-c53f468ae813334c225b18fa","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"596f845a43d7a997861347a6bbdfe900ef177b21daf6e5f5bc7a191ee6b9e7f8","afterSHA256":"596f845a43d7a997861347a6bbdfe900ef177b21daf6e5f5bc7a191ee6b9e7f8","reason":"Same source body in authored semantic page"},{"oldId":"b-e886bc7e9405d333552c200b","targetId":"b-e886bc7e9405d333552c200b","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"3692ed029bf31213ee6ddce712d05db3ed57c54d18122d873965128ee09e9c12","afterSHA256":"f56f575033bcab034622fd5bcf423ca70f6f99a0671bfa0c2557bc4ade38d310","reason":"Same source body in authored semantic page"},{"oldId":"b-dbdf933bb17f202936cb2f5f","targetId":"b-dbdf933bb17f202936cb2f5f","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"0bc30a0c85f509f96425ef6d503b1f4dda54adc0ee2017a6d11f91fd6398d7a1","afterSHA256":"6e59fe129adbd7f631cd6517b8715f8e88361fc81316790d51a971ff6a7ac9d1","reason":"Same source body in authored semantic page"},{"oldId":"b-ca48913a9e694006b1c0fdce","targetId":"b-ca48913a9e694006b1c0fdce","page":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","operation":"move","beforeSHA256":"239d41a1854eaf46c28660b8f1fafbd9e2dd5243ba3e50949f8b9548fb79b67f","afterSHA256":"239d41a1854eaf46c28660b8f1fafbd9e2dd5243ba3e50949f8b9548fb79b67f","reason":"Same source body in authored semantic page"},{"oldId":"b-6adbd0000a1e5a1c13e4d7ee","targetId":"b-6adbd0000a1e5a1c13e4d7ee","page":"reading-block-8413a612fc314b05806c00e9cf00fb7a","operation":"move","beforeSHA256":"e4fe0386a7ec4009e0b726ed0380c146b413771e54cc9b67fa42f3c17ddc9e69","afterSHA256":"e4fe0386a7ec4009e0b726ed0380c146b413771e54cc9b67fa42f3c17ddc9e69","reason":"Same source body in authored semantic page"},{"oldId":"b-ef6c1318eba04fa1a317c01d","targetId":"b-ef6c1318eba04fa1a317c01d","page":"reading-block-8413a612fc314b05806c00e9cf00fb7a","operation":"move","beforeSHA256":"62cd3c3e7472a4976a8c101608c68d04df6eb55e6ed8b1cdfe8b808e43846633","afterSHA256":"62cd3c3e7472a4976a8c101608c68d04df6eb55e6ed8b1cdfe8b808e43846633","reason":"Same source body in authored semantic page"},{"oldId":"b-dd6a11f3bdcbba47716b63e6","targetId":"b-dd6a11f3bdcbba47716b63e6","page":"reading-block-8413a612fc314b05806c00e9cf00fb7a","operation":"move","beforeSHA256":"b77c69f411f0cec66906efa93953096b72fee0517dd04ceb2eb4f2c14fca2c6c","afterSHA256":"b77c69f411f0cec66906efa93953096b72fee0517dd04ceb2eb4f2c14fca2c6c","reason":"Same source body in authored semantic page"},{"oldId":"b-3aeba4ddbb05bd9505470963","targetId":"b-3aeba4ddbb05bd9505470963","page":"reading-block-8413a612fc314b05806c00e9cf00fb7a","operation":"move","beforeSHA256":"df469b42a008cfb7ecd8a88fd7f7836c4bc0779d31028b4938705dc288908ff6","afterSHA256":"df469b42a008cfb7ecd8a88fd7f7836c4bc0779d31028b4938705dc288908ff6","reason":"Same source body in authored semantic page"},{"oldId":"b-d38830ef3b5d12cafd997184","targetId":"b-d38830ef3b5d12cafd997184","page":"reading-block-8413a612fc314b05806c00e9cf00fb7a","operation":"move","beforeSHA256":"ea717067584e344418a930c49862e5bea35e54c3e75453a5dc35674aa7112bb5","afterSHA256":"ea717067584e344418a930c49862e5bea35e54c3e75453a5dc35674aa7112bb5","reason":"Same source body in authored semantic page"},{"oldId":"b-579a0fec8d10ad0060edb442","targetId":"b-579a0fec8d10ad0060edb442","page":"reading-block-8413a612fc314b05806c00e9cf00fb7a","operation":"move","beforeSHA256":"fdde3520bab89e32b78dca4f14b82d41aa943c01e54d2b8a789f56ae0adbb053","afterSHA256":"fdde3520bab89e32b78dca4f14b82d41aa943c01e54d2b8a789f56ae0adbb053","reason":"Same source body in authored semantic 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enriched"},{"oldId":"b-3fcfbc1b621f9c6edf9b7dc6","targetId":"b-3fcfbc1b621f9c6edf9b7dc6","page":"reading-block-8413a612fc314b05806c00e9cf00fb7a","operation":"move","beforeSHA256":"b2da5a7d8caaa632c7ae9f9f6ce0a06fe464eecb40e6472dfe0da761208eb634","afterSHA256":"b2da5a7d8caaa632c7ae9f9f6ce0a06fe464eecb40e6472dfe0da761208eb634","reason":"Same source body in authored semantic page"},{"oldId":"b-f954f354de34ed8368eafad5","targetId":"b-f954f354de34ed8368eafad5","page":"reading-block-8413a612fc314b05806c00e9cf00fb7a","operation":"move","beforeSHA256":"4f70352dd5540e712df3eec48a1d8a256a043e13993dd8de8b43b7b9f446b8b8","afterSHA256":"4f70352dd5540e712df3eec48a1d8a256a043e13993dd8de8b43b7b9f446b8b8","reason":"Same source body in authored semantic 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[像素、边界与对象身份](/course/study/pixels-instances.html)","sha256":"30ab9f304366670818536cf73c98c66aa814e8e31ecdbffcf19a4d6e7e7f22de","chapter":{"id":"II","title":"区域、像素与实例"},"unit":{"id":"pixel-prediction-objective","title":"怎样直接学习一张像素类别地图？"},"page":{"id":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","title":"一张类别图怎样成为可训练的输出","number":2},"sectionTitle":"一张类别图怎样成为可训练的输出","currentQuestion":"一张类别图怎样成为可训练的输出","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"previousBlock":null,"nextBlock":"b-d76f1d331aa310461f13cdfc","prerequisites":[],"relatedBlocks":[]},{"id":"b-d76f1d331aa310461f13cdfc","type":"p","scope":"block-6ca34c15abaf4aeb9900af72759ebc28","url":"https://codingai-lec03.pages.dev/course/notebooks/2d81e2a1936043349eacb71c53c0defa.html#b-d76f1d331aa310461f13cdfc","content":"本册承接 [P36 的逐像素任务](/course/pages/l3-r2-p36.html)，解释 [LAB 11](https://deepnote.com/project/38755e4e-23f6-4f5f-8c68-8a2e4114b1c1/notebook/9e268706471944e3a59e6f568f9ce9a3) 为什么需要新的目标、损失和评价。先读 logits/目标/ignore，再用 8×8 算例区分前景 IoU、两类 mIoU 和像素准确率；最后看语义类别为何不能唯一给出实例身份。","sha256":"72798cbfc37e71e8b9dbbcfe3cfb8a7b0fc2d74531b251cdcb3e0c9989b9c37d","chapter":{"id":"II","title":"区域、像素与实例"},"unit":{"id":"pixel-prediction-objective","title":"怎样直接学习一张像素类别地图？"},"page":{"id":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","title":"一张类别图怎样成为可训练的输出","number":2},"sectionTitle":"一张类别图怎样成为可训练的输出","currentQuestion":"一张类别图怎样成为可训练的输出","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"previousBlock":"b-d68c0fe4646a89db1c8a2d5a","nextBlock":"b-21fe5755784d5232009cdd64","prerequisites":[{"id":"b-d68c0fe4646a89db1c8a2d5a","url":"#b-d68c0fe4646a89db1c8a2d5a","role":"problem-context"}],"relatedBlocks":[]},{"id":"b-21fe5755784d5232009cdd64","type":"p","scope":"block-6ca34c15abaf4aeb9900af72759ebc28","url":"https://codingai-lec03.pages.dev/course/notebooks/2d81e2a1936043349eacb71c53c0defa.html#b-21fe5755784d5232009cdd64","content":"希望先看结果，可读 [RGB 读出与 FCN 的对照](/course/blocks/pixel-model-positive-result.html)；希望核一个指标，可引用 [0.667 与 0.75 的完整算例](/course/blocks/mask-iou-worked-example.html)。读完应能解释“框对了但边界仍错”和“所有杯子像素对了但实例仍未分开”这两个缺口。","sha256":"93743e4257248bf9219358b363aae08572036e7ccafb37b6917bd45eeacfbe96","chapter":{"id":"II","title":"区域、像素与实例"},"unit":{"id":"pixel-prediction-objective","title":"怎样直接学习一张像素类别地图？"},"page":{"id":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","title":"一张类别图怎样成为可训练的输出","number":2},"sectionTitle":"一张类别图怎样成为可训练的输出","currentQuestion":"一张类别图怎样成为可训练的输出","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"previousBlock":"b-d76f1d331aa310461f13cdfc","nextBlock":"b-97a054a12812cb451ba3a866","prerequisites":[{"id":"b-d68c0fe4646a89db1c8a2d5a","url":"#b-d68c0fe4646a89db1c8a2d5a","role":"problem-context"}],"relatedBlocks":[]},{"id":"b-97a054a12812cb451ba3a866","type":"p","scope":"block-6ca34c15abaf4aeb9900af72759ebc28","url":"https://codingai-lec03.pages.dev/course/notebooks/2d81e2a1936043349eacb71c53c0defa.html#b-97a054a12812cb451ba3a866","content":"坐标采样的动手入口是 [LAB 03](https://deepnote.com/project/38755e4e-23f6-4f5f-8c68-8a2e4114b1c1/notebook/49a2c030eafa4e1db6fc4f1a08c3810a)；多尺度和集合匹配留在本册后部选读。它们不要求在理解像素预测前先完成。","sha256":"ad5c18536ebaaed1683a9cbbc42e20e2f10a94f3ad582f81270f89de1719a98f","chapter":{"id":"II","title":"区域、像素与实例"},"unit":{"id":"pixel-prediction-objective","title":"怎样直接学习一张像素类别地图？"},"page":{"id":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","title":"一张类别图怎样成为可训练的输出","number":2},"sectionTitle":"一张类别图怎样成为可训练的输出","currentQuestion":"一张类别图怎样成为可训练的输出","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"previousBlock":"b-21fe5755784d5232009cdd64","nextBlock":"b-794e274a9ee045ebec4c1393","prerequisites":[{"id":"b-d68c0fe4646a89db1c8a2d5a","url":"#b-d68c0fe4646a89db1c8a2d5a","role":"problem-context"}],"relatedBlocks":[]},{"id":"b-794e274a9ee045ebec4c1393","type":"p","scope":"block-6ca34c15abaf4aeb9900af72759ebc28","url":"https://codingai-lec03.pages.dev/course/notebooks/2d81e2a1936043349eacb71c53c0defa.html#b-794e274a9ee045ebec4c1393","content":"一个框可以同时包住杯身、杯把和杯把中的背景。框坐标全对，仍不代表我们知道每个像素属于谁。若两只杯子接触，语义分割可以把它们都标成“杯子”，但要分别计数和操作，就还需区分实例身份。这里不是同一个答案换显示颜色，而是输出空间和监督单位发生了变化。","sha256":"5409b0105bb5ec9dc3241c580e59c54772c6e8b9d8dbcfe5caf959343ea238a6","chapter":{"id":"II","title":"区域、像素与实例"},"unit":{"id":"pixel-prediction-objective","title":"怎样直接学习一张像素类别地图？"},"page":{"id":"reading-block-6ca34c15abaf4aeb9900af72759ebc28","title":"一张类别图怎样成为可训练的输出","number":2},"sectionTitle":"一张类别图怎样成为可训练的输出","currentQuestion":"一张类别图怎样成为可训练的输出","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"previousBlock":"b-97a054a12812cb451ba3a866","nextBlock":"b-6d586f2f83d71b3286164507","prerequisites":[{"id":"b-d68c0fe4646a89db1c8a2d5a","url":"#b-d68c0fe4646a89db1c8a2d5a","role":"problem-context"}],"relatedBlocks":[]},{"id":"b-6d586f2f83d71b3286164507","type":"h2","scope":"block-6ca34c15abaf4aeb9900af72759ebc28","url":"https://codingai-lec03.pages.dev/course/notebooks/2d81e2a1936043349eacb71c53c0defa.html#b-6d586f2f83d71b3286164507","content":"## 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