Restructure json data

Question

I have a JSON with following structure:

    {
    "id": 2,
    "image_id": 2,
    "segmentation": [
        [
            913.0,
            659.5,
            895.0,
        ],
        [   
            658.5,
            875.0,
            652.5,
            659.5
        ],
    ],
    "iscrowd": 0,
    "bbox": [
        4.5,
        406.5,
        1098.0,
        1096.0
    ],
    "area": 579348.0,
    "category_id": 0
},

Now I need to split each entry it into two separate entries, like these:

    {
    "id": 2,
    "image_id": 2,
    "segmentation": [
        [
            658.5,
            875.0,
            652.5,
            659.5
        ],
    ],
    "iscrowd": 0,
    "bbox": [
        4.5,
        406.5,
        1098.0,
        1096.0
    ],
    "area": 579348.0,
    "category_id": 0
    },
    {
    "id": 3,
    "image_id": 2,
    "segmentation": [
        [
            913.0,
            659.5,
            895.0,
        ],
    ],
    "iscrowd": 0,
    "bbox": [
        4.5,
        406.5,
        1098.0,
        1096.0
    ],
    "area": 579348.0,
    "category_id": 0
},

So that each new entry has the same image_id and iscrowd, bbox, area & category_id as the original entry, however gets new (incremental) id, and has only one segmentations:[] . So if the original entry had 15 segmentations, the code would split it into 15 entries with unique IDs.

Any tips how? I have found some posts on how to merge based on key value, but not how to split.

Answer 1

import json

new_json = []
ids = 0


for i in original_json:
    segms = i["segmentation"]
    for j in segms:
        dummy = {}
        for k in i:
            dummy[k] = i[k]
        dummy["id"] = ids
        dummy["segmentation"] = j
        ids+=1
        new_json.append(dummy)

with open("new_json_file.json", 'w') as f:
    json.dump(new_json, f)

Hope this helps

Answer 2

So the code provided by @iamtrappedman sort of works:

test_loc = "/content/TEST.json"
with open(test_loc) as j_f:
  original_json = json.load(j_f)

  segms = original_json[0]["segmentation"]
  new_json = []

  for i in segms:
    original_json[0]["segmentation"] = i
    new_json.append(original_json)

  with open("new_json_file.json", "w") as f:
    json.dump(new_json, f,indent=4)

If I input following JSON:

[
{
    "id": 0,
    "image_id": 0,
    "segmentation": [
        [
            465.0,
            1198.5,
            432.0,
            1190.5
        ],
        [
            525.0,
            2424.5,
            1257.0,
            2578.5
        ]
    ],
    "iscrowd": 0,
    "bbox": [
        0.5,
        407.5,
        869.0,
        791.0
    ],
    "area": 425968.25,
    "category_id": 0
}
]

I get a JSON thats splitted, however both entries are identical:

[
[
    {
        "area": 425968.25,
        "bbox": [
            0.5,
            407.5,
            869.0,
            791.0
        ],
        "category_id": 0,
        "id": 0,
        "image_id": 0,
        "iscrowd": 0,
        "segmentation": [
            525.0,
            2424.5,
            1257.0,
            2578.5
        ]
    }
],
[
    {
        "area": 425968.25,
        "bbox": [
            0.5,
            407.5,
            869.0,
            791.0
        ],
        "category_id": 0,
        "id": 0,
        "image_id": 0,
        "iscrowd": 0,
        "segmentation": [
            525.0,
            2424.5,
            1257.0,
            2578.5
        ]
    }
]
]

EDIT Now for JSON with two annotations:

[
{
    "id": 0,
    "image_id": 0,
    "segmentation": [
        [
            465.0,
            1198.5,
            432.0,
            1190.5
        ],
        [
            525.0,
            2424.5,
            1257.0,
            2578.5
        ]
    ],
    "iscrowd": 0,
    "bbox": [
        0.5,
        407.5,
        869.0,
        791.0
    ],
    "area": 425968.25,
    "category_id": 0
},
{
    "id": 1,
    "image_id": 2,
    "segmentation": [
        [
            4241.0,
            14.5,
            141.0,
            7557.5
        ],
        [
            578.0,
            2424.5,
            141.0,
            965.5
        ]
    ],
    "iscrowd": 0,
    "bbox": [
        0.5,
        407.5,
        869.0,
        791.0
    ],
    "area": 425968.25,
    "category_id": 0
}
]

It does not split the annotations but duplicates them

[
[
    {
        "id": 0,
        "image_id": 0,
        "segmentation": [
            525.0,
            2424.5,
            1257.0,
            2578.5
        ],
        "iscrowd": 0,
        "bbox": [
            0.5,
            407.5,
            869.0,
            791.0
        ],
        "area": 425968.25,
        "category_id": 0
    },
    {
        "id": 1,
        "image_id": 2,
        "segmentation": [
            [
                4241.0,
                14.5,
                141.0,
                7557.5
            ],
            [
                578.0,
                2424.5,
                141.0,
                965.5
            ]
        ],
        "iscrowd": 0,
        "bbox": [
            0.5,
            407.5,
            869.0,
            791.0
        ],
        "area": 425968.25,
        "category_id": 0
    }
],
[
    {
        "id": 0,
        "image_id": 0,
        "segmentation": [
            525.0,
            2424.5,
            1257.0,
            2578.5
        ],
        "iscrowd": 0,
        "bbox": [
            0.5,
            407.5,
            869.0,
            791.0
        ],
        "area": 425968.25,
        "category_id": 0
    },
    {
        "id": 1,
        "image_id": 2,
        "segmentation": [
            [
                4241.0,
                14.5,
                141.0,
                7557.5
            ],
            [
                578.0,
                2424.5,
                141.0,
                965.5
            ]
        ],
        "iscrowd": 0,
        "bbox": [
            0.5,
            407.5,
            869.0,
            791.0
        ],
        "area": 425968.25,
        "category_id": 0
    }
]
]