{
  "id": 72697,
  "title": "Which Image size do you use?",
  "url": "/competitions/quickdraw-doodle-recognition/discussion/72697",
  "author_name": "hahaha",
  "post_date": "2018-11-26T11:54:09.055000",
  "votes": 3,
  "comment_count": 30,
  "views": 0,
  "content": "<p>To get beyond LB0.93 , I guess I need to increase image size.  But large size image takes really long :( \nIs it necessary to use equal or larger than 224x224 size to get more accuracy?</p>",
  "messages": [
    {
      "id": 427920,
      "postDate": "2018-11-26T11:54:09.057Z",
      "content": "<p>To get beyond LB0.93 , I guess I need to increase image size.  But large size image takes really long :( \nIs it necessary to use equal or larger than 224x224 size to get more accuracy?</p>",
      "rawMarkdown": "To get beyond LB0.93 , I guess I need to increase image size.  But large size image takes really long :( \nIs it necessary to use equal or larger than 224x224 size to get more accuracy?",
      "votes": 3
    },
    {
      "id": 428247,
      "postDate": "2018-11-27T01:19:05.673Z",
      "content": "<p>I used smaller image sizes at first 64px then continue fine-tuning at 128px. I don't think you need to increase the image size to get beyond LB 0.93, instead focus on bigger batch sizes and work on a good training lr schedule.</p>",
      "rawMarkdown": "I used smaller image sizes at first 64px then continue fine-tuning at 128px. I don't think you need to increase the image size to get beyond LB 0.93, instead focus on bigger batch sizes and work on a good training lr schedule.",
      "votes": 1,
      "replies": [
        {
          "id": 428568,
          "postDate": "2018-11-27T13:52:03.863Z",
          "content": "<p>Is  fine tunning  better than training 128size from beginning?\nAny loss of accuracy? </p>",
          "rawMarkdown": "Is  fine tunning  better than training 128size from beginning?\nAny loss of accuracy? "
        },
        {
          "id": 428687,
          "postDate": "2018-11-27T18:06:39.577Z",
          "content": "<p>No loss in accuracy. From my experiments its faster to train this way overall and usually the model will be less prone to overfitting after re-sizing to 128px.</p>",
          "rawMarkdown": "No loss in accuracy. From my experiments its faster to train this way overall and usually the model will be less prone to overfitting after re-sizing to 128px."
        },
        {
          "id": 428689,
          "postDate": "2018-11-27T18:09:30.280Z",
          "content": "<p>You mean you train first using 64px then fine-tune it to 128px. question, how many epochs are you using and its batch size for 64px?</p>",
          "rawMarkdown": "You mean you train first using 64px then fine-tune it to 128px. question, how many epochs are you using and its batch size for 64px?",
          "votes": 10
        },
        {
          "id": 429509,
          "postDate": "2018-11-29T00:33:31.337Z",
          "content": "<p>Thanks for sharing your experience! </p>",
          "rawMarkdown": "Thanks for sharing your experience! "
        }
      ]
    },
    {
      "id": 427979,
      "postDate": "2018-11-26T14:17:21.417Z",
      "content": "<p>I was able to use 128x128 to get 94.3 and I presume others may have gotten higher on similar image size. What are size are you using at the moment?</p>",
      "rawMarkdown": "I was able to use 128x128 to get 94.3 and I presume others may have gotten higher on similar image size. What are size are you using at the moment?",
      "votes": 1,
      "replies": [
        {
          "id": 427985,
          "postDate": "2018-11-26T14:27:25.467Z",
          "content": "<p>what kind of NN are you using to achieve 0.943? is it a single model or ensemble?</p>",
          "rawMarkdown": "what kind of NN are you using to achieve 0.943? is it a single model or ensemble?",
          "votes": 1
        },
        {
          "id": 428209,
          "postDate": "2018-11-26T23:27:14.790Z",
          "content": "<p>A single Xception model obtains that score - nothing really fancy actually (as already mentioned by Heng in his other post).</p>",
          "rawMarkdown": "A single Xception model obtains that score - nothing really fancy actually (as already mentioned by Heng in his other post)."
        },
        {
          "id": 428216,
          "postDate": "2018-11-26T23:40:07.957Z",
          "content": "<p>I used 64 or 96size. If 128x128 size is sufficent, I will try it first. Thanks!</p>",
          "rawMarkdown": "I used 64 or 96size. If 128x128 size is sufficent, I will try it first. Thanks!"
        },
        {
          "id": 428609,
          "postDate": "2018-11-27T15:19:10.960Z",
          "content": "<p><a href=\"/wilanw\">@wilanw</a> may I ask how long does it take for your Xception to complete 1 epoch of 50M training data? Because I use Xception with 128x128 too, but my model is super slow (i.e. 1 week+ for 50M data)</p>",
          "rawMarkdown": "@wilanw may I ask how long does it take for your Xception to complete 1 epoch of 50M training data? Because I use Xception with 128x128 too, but my model is super slow (i.e. 1 week+ for 50M data)",
          "votes": 1
        },
        {
          "id": 428660,
          "postDate": "2018-11-27T17:10:54.680Z",
          "content": "<p>is your Xception model based on Pytorch or keras?</p>",
          "rawMarkdown": "is your Xception model based on Pytorch or keras?",
          "votes": 1
        },
        {
          "id": 428858,
          "postDate": "2018-11-28T01:34:20.853Z",
          "content": "<p>It's based on Keras - using the pretrained imagenet weights as well. </p>",
          "rawMarkdown": "It's based on Keras - using the pretrained imagenet weights as well. ",
          "votes": 1
        },
        {
          "id": 428974,
          "postDate": "2018-11-28T06:52:19.673Z",
          "rawMarkdown": "",
          "isDeleted": true
        }
      ]
    },
    {
      "id": 428220,
      "postDate": "2018-11-26T23:52:02.043Z",
      "content": "<p>Try to train on 64, then keep finetuning on larger images. The image size things are a kind of marginal benefit.\n:D</p>",
      "rawMarkdown": "Try to train on 64, then keep finetuning on larger images. The image size things are a kind of marginal benefit.\n:D",
      "votes": 2,
      "replies": [
        {
          "id": 428239,
          "postDate": "2018-11-27T00:59:59.360Z",
          "content": "<p>How do you change the image size for fine tuning?</p>",
          "rawMarkdown": "How do you change the image size for fine tuning?"
        },
        {
          "id": 428571,
          "postDate": "2018-11-27T13:57:13.503Z",
          "content": "<p>I’m wonder whether fine tunning have any loss of accuracy or not</p>",
          "rawMarkdown": "I’m wonder whether fine tunning have any loss of accuracy or not"
        },
        {
          "id": 428648,
          "postDate": "2018-11-27T16:54:55.970Z",
          "content": "<p>64 --&gt; 96 --&gt; 128 --&gt; larger...</p>",
          "rawMarkdown": "64 --&gt; 96 --&gt; 128 --&gt; larger..."
        }
      ]
    },
    {
      "id": 431870,
      "postDate": "2018-12-03T03:35:01.607Z",
      "content": "<p>not necessary for 0.93 I think. For my previous experiment, 25k/class training samples + 96*96size, no tta, no augmentation can get 0.935</p>",
      "rawMarkdown": "not necessary for 0.93 I think. For my previous experiment, 25k/class training samples + 96*96size, no tta, no augmentation can get 0.935"
    },
    {
      "id": 430719,
      "postDate": "2018-11-30T22:06:28.110Z",
      "content": "<p>When I resized to bigger image size, I just never could recover and beat the previous score. </p>",
      "rawMarkdown": "When I resized to bigger image size, I just never could recover and beat the previous score. "
    },
    {
      "id": 428815,
      "postDate": "2018-11-27T23:50:04.433Z",
      "content": "<p>When I finetuned my already pretty good model trained on image size 128*128 with image size 224*224, I got this strange phenomenon. I tried various learning rates but the finetuned model couldn't recover the previous score or improve it. </p>",
      "rawMarkdown": "When I finetuned my already pretty good model trained on image size 128*128 with image size 224*224, I got this strange phenomenon. I tried various learning rates but the finetuned model couldn't recover the previous score or improve it. ",
      "replies": [
        {
          "id": 428842,
          "postDate": "2018-11-28T00:47:02.227Z",
          "content": "<p>@HuyenNguyen, I had the same problem when I went from 80x80 image size to 128x128 but trained the 2nd model from scratch, for longer, and more data. So I am not sure what the issue is. Like you I changed my learning rate, batch size etc. but did not help still got lower score than the 80x80.</p>",
          "rawMarkdown": "@HuyenNguyen, I had the same problem when I went from 80x80 image size to 128x128 but trained the 2nd model from scratch, for longer, and more data. So I am not sure what the issue is. Like you I changed my learning rate, batch size etc. but did not help still got lower score than the 80x80.",
          "votes": 1
        },
        {
          "id": 429511,
          "postDate": "2018-11-29T00:36:56.163Z",
          "content": "<p>Oh , I confused.... did you check optimizer or lr schedule? </p>",
          "rawMarkdown": "Oh , I confused.... did you check optimizer or lr schedule? "
        },
        {
          "id": 430640,
          "postDate": "2018-11-30T19:11:34.397Z",
          "content": "<p>224*224 is too big for such huge dataset... I wonder how you guys manage to train with this size in reasonnable amount of time. </p>",
          "rawMarkdown": "224*224 is too big for such huge dataset... I wonder how you guys manage to train with this size in reasonnable amount of time. "
        },
        {
          "id": 431859,
          "postDate": "2018-12-03T02:53:52.230Z",
          "content": "<p>omg.. I also have same problem when I finetunned 128x128 image from 96x96 images. </p>",
          "rawMarkdown": "omg.. I also have same problem when I finetunned 128x128 image from 96x96 images. "
        }
      ]
    },
    {
      "id": 428243,
      "postDate": "2018-11-27T01:05:51.450Z",
      "content": "<p>I used a variety of image sizes, including 96, 128, 144 and 196. At this point my model performance increases with size, but my models haven't converged yet for size 196.</p>",
      "rawMarkdown": "I used a variety of image sizes, including 96, 128, 144 and 196. At this point my model performance increases with size, but my models haven't converged yet for size 196.",
      "replies": [
        {
          "id": 428373,
          "postDate": "2018-11-27T06:58:10.473Z",
          "content": "<p>When you use larger image size, do you reduce the learning rate? </p>",
          "rawMarkdown": "When you use larger image size, do you reduce the learning rate? "
        },
        {
          "id": 428570,
          "postDate": "2018-11-27T13:53:58.483Z",
          "content": "<p>How many times did you need to get the final result of 144 size?</p>",
          "rawMarkdown": "How many times did you need to get the final result of 144 size?"
        }
      ]
    },
    {
      "id": 427926,
      "postDate": "2018-11-26T12:04:52.413Z",
      "content": "<p>I used 128x128 so far. I am thinking about increasing the input size too...</p>",
      "rawMarkdown": "I used 128x128 so far. I am thinking about increasing the input size too...",
      "replies": [
        {
          "id": 428215,
          "postDate": "2018-11-26T23:38:57.763Z",
          "content": "<p>Until now I used 64 or 96 size. Thanks for you comment! </p>",
          "rawMarkdown": "Until now I used 64 or 96 size. Thanks for you comment! "
        }
      ]
    },
    {
      "id": 430215,
      "postDate": "2018-11-30T03:12:00.027Z",
      "rawMarkdown": "",
      "votes": 2,
      "isDeleted": true
    }
  ],
  "comments": [
    {
      "id": 428247,
      "author_name": "James Requa",
      "author_url": "",
      "post_date": "2018-11-27T01:19:05.673000",
      "content": "<p>I used smaller image sizes at first 64px then continue fine-tuning at 128px. I don't think you need to increase the image size to get beyond LB 0.93, instead focus on bigger batch sizes and work on a good training lr schedule.</p>",
      "votes": 1,
      "replies": [
        {
          "id": 428568,
          "author_name": "hahaha",
          "author_url": "",
          "post_date": "2018-11-27T13:52:03.863000",
          "content": "<p>Is  fine tunning  better than training 128size from beginning?\nAny loss of accuracy? </p>",
          "votes": 0,
          "replies": []
        },
        {
          "id": 428687,
          "author_name": "James Requa",
          "author_url": "",
          "post_date": "2018-11-27T18:06:39.577000",
          "content": "<p>No loss in accuracy. From my experiments its faster to train this way overall and usually the model will be less prone to overfitting after re-sizing to 128px.</p>",
          "votes": 0,
          "replies": []
        },
        {
          "id": 428689,
          "author_name": "",
          "author_url": "",
          "post_date": "2018-11-27T18:09:30.280000",
          "content": "<p>You mean you train first using 64px then fine-tune it to 128px. question, how many epochs are you using and its batch size for 64px?</p>",
          "votes": 10,
          "replies": []
        },
        {
          "id": 429509,
          "author_name": "hahaha",
          "author_url": "",
          "post_date": "2018-11-29T00:33:31.337000",
          "content": "<p>Thanks for sharing your experience! </p>",
          "votes": 0,
          "replies": []
        }
      ]
    },
    {
      "id": 427979,
      "author_name": "wilan",
      "author_url": "",
      "post_date": "2018-11-26T14:17:21.417000",
      "content": "<p>I was able to use 128x128 to get 94.3 and I presume others may have gotten higher on similar image size. What are size are you using at the moment?</p>",
      "votes": 1,
      "replies": [
        {
          "id": 427985,
          "author_name": "",
          "author_url": "",
          "post_date": "2018-11-26T14:27:25.467000",
          "content": "<p>what kind of NN are you using to achieve 0.943? is it a single model or ensemble?</p>",
          "votes": 1,
          "replies": []
        },
        {
          "id": 428209,
          "author_name": "wilan",
          "author_url": "",
          "post_date": "2018-11-26T23:27:14.790000",
          "content": "<p>A single Xception model obtains that score - nothing really fancy actually (as already mentioned by Heng in his other post).</p>",
          "votes": 0,
          "replies": []
        },
        {
          "id": 428216,
          "author_name": "hahaha",
          "author_url": "",
          "post_date": "2018-11-26T23:40:07.957000",
          "content": "<p>I used 64 or 96size. If 128x128 size is sufficent, I will try it first. Thanks!</p>",
          "votes": 0,
          "replies": []
        },
        {
          "id": 428609,
          "author_name": "Neuron Engineer",
          "author_url": "",
          "post_date": "2018-11-27T15:19:10.960000",
          "content": "<p><a href=\"/wilanw\">@wilanw</a> may I ask how long does it take for your Xception to complete 1 epoch of 50M training data? Because I use Xception with 128x128 too, but my model is super slow (i.e. 1 week+ for 50M data)</p>",
          "votes": 1,
          "replies": []
        },
        {
          "id": 428660,
          "author_name": "",
          "author_url": "",
          "post_date": "2018-11-27T17:10:54.680000",
          "content": "<p>is your Xception model based on Pytorch or keras?</p>",
          "votes": 1,
          "replies": []
        },
        {
          "id": 428858,
          "author_name": "wilan",
          "author_url": "",
          "post_date": "2018-11-28T01:34:20.853000",
          "content": "<p>It's based on Keras - using the pretrained imagenet weights as well. </p>",
          "votes": 1,
          "replies": []
        },
        {
          "id": 428974,
          "author_name": "",
          "author_url": "",
          "post_date": "2018-11-28T06:52:19.673000",
          "content": "",
          "votes": 0,
          "replies": []
        }
      ]
    },
    {
      "id": 428220,
      "author_name": "Kulbear",
      "author_url": "",
      "post_date": "2018-11-26T23:52:02.043000",
      "content": "<p>Try to train on 64, then keep finetuning on larger images. The image size things are a kind of marginal benefit.\n:D</p>",
      "votes": 2,
      "replies": [
        {
          "id": 428239,
          "author_name": "YaGana Sheriff-Hussaini",
          "author_url": "",
          "post_date": "2018-11-27T00:59:59.360000",
          "content": "<p>How do you change the image size for fine tuning?</p>",
          "votes": 0,
          "replies": []
        },
        {
          "id": 428571,
          "author_name": "hahaha",
          "author_url": "",
          "post_date": "2018-11-27T13:57:13.503000",
          "content": "<p>I’m wonder whether fine tunning have any loss of accuracy or not</p>",
          "votes": 0,
          "replies": []
        },
        {
          "id": 428648,
          "author_name": "Kulbear",
          "author_url": "",
          "post_date": "2018-11-27T16:54:55.970000",
          "content": "<p>64 --&gt; 96 --&gt; 128 --&gt; larger...</p>",
          "votes": 0,
          "replies": []
        }
      ]
    },
    {
      "id": 431870,
      "author_name": "Yiheng Wang",
      "author_url": "",
      "post_date": "2018-12-03T03:35:01.607000",
      "content": "<p>not necessary for 0.93 I think. For my previous experiment, 25k/class training samples + 96*96size, no tta, no augmentation can get 0.935</p>",
      "votes": 0,
      "replies": []
    },
    {
      "id": 430719,
      "author_name": "HuyenNguyen",
      "author_url": "",
      "post_date": "2018-11-30T22:06:28.110000",
      "content": "<p>When I resized to bigger image size, I just never could recover and beat the previous score. </p>",
      "votes": 0,
      "replies": []
    },
    {
      "id": 428815,
      "author_name": "HuyenNguyen",
      "author_url": "",
      "post_date": "2018-11-27T23:50:04.433000",
      "content": "<p>When I finetuned my already pretty good model trained on image size 128*128 with image size 224*224, I got this strange phenomenon. I tried various learning rates but the finetuned model couldn't recover the previous score or improve it. </p>",
      "votes": 0,
      "replies": [
        {
          "id": 428842,
          "author_name": "YaGana Sheriff-Hussaini",
          "author_url": "",
          "post_date": "2018-11-28T00:47:02.227000",
          "content": "<p>@HuyenNguyen, I had the same problem when I went from 80x80 image size to 128x128 but trained the 2nd model from scratch, for longer, and more data. So I am not sure what the issue is. Like you I changed my learning rate, batch size etc. but did not help still got lower score than the 80x80.</p>",
          "votes": 1,
          "replies": []
        },
        {
          "id": 429511,
          "author_name": "hahaha",
          "author_url": "",
          "post_date": "2018-11-29T00:36:56.163000",
          "content": "<p>Oh , I confused.... did you check optimizer or lr schedule? </p>",
          "votes": 0,
          "replies": []
        },
        {
          "id": 430640,
          "author_name": "Serigne ",
          "author_url": "",
          "post_date": "2018-11-30T19:11:34.397000",
          "content": "<p>224*224 is too big for such huge dataset... I wonder how you guys manage to train with this size in reasonnable amount of time. </p>",
          "votes": 0,
          "replies": []
        },
        {
          "id": 431859,
          "author_name": "hahaha",
          "author_url": "",
          "post_date": "2018-12-03T02:53:52.230000",
          "content": "<p>omg.. I also have same problem when I finetunned 128x128 image from 96x96 images. </p>",
          "votes": 0,
          "replies": []
        }
      ]
    },
    {
      "id": 428243,
      "author_name": "Peiyuan Liao",
      "author_url": "",
      "post_date": "2018-11-27T01:05:51.450000",
      "content": "<p>I used a variety of image sizes, including 96, 128, 144 and 196. At this point my model performance increases with size, but my models haven't converged yet for size 196.</p>",
      "votes": 0,
      "replies": [
        {
          "id": 428373,
          "author_name": "HuyenNguyen",
          "author_url": "",
          "post_date": "2018-11-27T06:58:10.473000",
          "content": "<p>When you use larger image size, do you reduce the learning rate? </p>",
          "votes": 0,
          "replies": []
        },
        {
          "id": 428570,
          "author_name": "hahaha",
          "author_url": "",
          "post_date": "2018-11-27T13:53:58.483000",
          "content": "<p>How many times did you need to get the final result of 144 size?</p>",
          "votes": 0,
          "replies": []
        }
      ]
    },
    {
      "id": 427926,
      "author_name": "beluga",
      "author_url": "",
      "post_date": "2018-11-26T12:04:52.413000",
      "content": "<p>I used 128x128 so far. I am thinking about increasing the input size too...</p>",
      "votes": 0,
      "replies": [
        {
          "id": 428215,
          "author_name": "hahaha",
          "author_url": "",
          "post_date": "2018-11-26T23:38:57.763000",
          "content": "<p>Until now I used 64 or 96 size. Thanks for you comment! </p>",
          "votes": 0,
          "replies": []
        }
      ]
    },
    {
      "id": 430215,
      "author_name": "",
      "author_url": "",
      "post_date": "2018-11-30T03:12:00.027000",
      "content": "",
      "votes": 2,
      "replies": []
    }
  ],
  "raw_markdown_by_id": {
    "427920": "To get beyond LB0.93 , I guess I need to increase image size.  But large size image takes really long :( \nIs it necessary to use equal or larger than 224x224 size to get more accuracy?",
    "428247": "I used smaller image sizes at first 64px then continue fine-tuning at 128px. I don't think you need to increase the image size to get beyond LB 0.93, instead focus on bigger batch sizes and work on a good training lr schedule.",
    "427979": "I was able to use 128x128 to get 94.3 and I presume others may have gotten higher on similar image size. What are size are you using at the moment?",
    "428220": "Try to train on 64, then keep finetuning on larger images. The image size things are a kind of marginal benefit.\n:D",
    "431870": "not necessary for 0.93 I think. For my previous experiment, 25k/class training samples + 96*96size, no tta, no augmentation can get 0.935",
    "430719": "When I resized to bigger image size, I just never could recover and beat the previous score. ",
    "428815": "When I finetuned my already pretty good model trained on image size 128*128 with image size 224*224, I got this strange phenomenon. I tried various learning rates but the finetuned model couldn't recover the previous score or improve it. ",
    "428243": "I used a variety of image sizes, including 96, 128, 144 and 196. At this point my model performance increases with size, but my models haven't converged yet for size 196.",
    "427926": "I used 128x128 so far. I am thinking about increasing the input size too...",
    "430215": ""
  }
}