Subset with Bounding Boxes (600 classes), Object Segmentations, and Visual Relationships

These annotation files cover the 600 boxable object classes, and span the 1,743,042 training images where we annotated bounding boxes, object segmentations, and visual relationships, as well as the full validation (41,620 images) and test (125,436 images) sets.

Trouble downloading the pixels? Let us know.

Subset with Image-Level Labels (19,959 classes)

These annotation files cover all object classes. In the train set, the human-verified labels span 6,287,678 images, while the machine-generated labels span 8,949,445 images.
The image IDs below list all images that have human-verified labels.
The annotation files span the full validation (41,620 images) and test (125,436 images) sets.

Trouble downloading the pixels? Let us know.

Complete Open Images

The full set of 9,178,275 images.

Trouble downloading the pixels? Let us know.

Open Images Extended

Data Formats

Bounding boxes

Each row defines one bounding box.

ImageID,Source,LabelName,Confidence,XMin,XMax,YMin,YMax,IsOccluded,IsTruncated,IsGroupOf,IsDepiction,IsInside
0001eeaf4aed83f9,xclick,/m/0cmf2,1,0.022673031,0.9642005,0.07103825,0.80054647,0,0,0,0,0
000595fe6fee6369,xclick,/m/02xwb,1,0.45655376,0.6097202,0.20399113,0.50554323,0,0,1,0,0
00075905539074f2,xclick,/m/04yx4,1,0.020477816,0.32935154,0.0956023,0.665392,0,0,0,1,0
000a1249af2bc5f0,xclick,/m/09j2d,1,0.56911767,0.99852943,0.0022172949,0.93569845,1,1,0,0,0
...

• ImageID: the image this box lives in.
• Source: indicates how the box was made:
  • xclick are manually drawn boxes using the method presented in [1].
  • activemil are boxes produced using an enhanced version of the method [2]. These are human verified to be accurate at IoU>0.7.
• LabelName: the MID of the object class this box belongs to.
• Confidence: a dummy value, always 1.
• XMin, XMax, YMin, YMax: coordinates of the box, in normalized image coordinates. XMin is in [0,1], where 0 is the leftmost pixel, and 1 is the rightmost pixel in the image. Y coordinates go from the top pixel (0) to the bottom pixel (1).

The attributes have the following definitions:

• IsOccluded: Indicates that the object is occluded by another object in the image.
• IsTruncated: Indicates that the object extends beyond the boundary of the image.
• IsGroupOf: Indicates that the box spans a group of objects (e.g., a bed of flowers or a crowd of people). We asked annotators to use this tag for cases with more than 5 instances which are heavily occluding each other and are physically touching.
• IsDepiction: Indicates that the object is a depiction (e.g., a cartoon or drawing of the object, not a real physical instance).
• IsInside: Indicates a picture taken from the inside of the object (e.g., a car interior or inside of a building).

For each of them, value 1 indicates present, 0 not present, and -1 unknown.

Instance segmentation masks

The masks information is stored in two files:

• Individual mask images, with information encoded in the filename.
• A comma-separated-values (CSV) file with additional information (masks_data.csv).

The masks images are PNG binary images, where non-zero pixels belong to a single object instance and zero pixels are background. The file names look as follows (random 5 examples):

e88da03f2d80f1a1_m019jd_e16d01b9.png
540c5536e95a3282_m014j1m_b00fa52e.png
1c84bdd61fa3b883_m06m11_62ef2388.png
663389d2c9d562d8_m04_sv_7e23f2a5.png
072b8fd82919ab3e_m06mf6_dd70f221.png

The format of .zip archives names is the following: each <subset>_<suffix>.zip contains all masks for all images with the first characted of ImageID equal to <suffix>. The value of <suffix> is from 0-9 and a-f.

Each row in masks_data.csv describes one instance, using similar conventions as the boxes CSV data file.

MaskPath,ImageID,LabelName,BoxID,BoxXMin,BoxXMax,BoxYMin,BoxYMax,PredictedIoU,Clicks
25adb319ebc72921_m02mqfb_8423aba8.png,25adb319ebc72921,/m/02mqfb,8423aba8,0.000000,0.998438,0.089062,0.770312,0.62821,0.15808 0.26206 1;0.90333 0.41076 0;0.17578 0.66566 1;0.00761 0.23197 1;0.07918 0.26058 0;0.31792 0.47737 1;0.12858 0.59262 0;0.73229 0.34016 1;0.01865 0.20001 1;0.52214 0.31037 0;0.83596 0.28105 1;0.23418 0.60177 0
0a419be97dec2fa3_m02mqfb_8ad2c442.png,0a419be97dec2fa3,/m/02mqfb,8ad2c442,0.057813,0.943750,0.056250,0.960938,0.87836,0.89971 0.08481 1;0.20175 0.90471 0;0.11511 0.89990 0;0.94728 0.28410 0;0.19611 0.85369 0;0.07672 0.87857 1;0.82215 0.62642 0;0.13916 0.92650 1;0.51738 0.48419 1
8eef6e54789ce66d_m02mqfb_83dae39c.png,8eef6e54789ce66d,/m/02mqfb,83dae39c,0.037500,0.978750,0.129688,0.925000,0.70206,0.40219 0.16838 1;0.56758 0.65286 1;0.08311 0.90762 1;0.20840 0.56515 1;0.43336 0.23679 0;0.24689 0.43426 0;0.49292 0.65762 1;0.31383 0.51431 0;0.07137 0.86214 0;0.68160 0.38210 1;0.69462 0.59568 0
...

• MaskPath: name of the corresponding mask image.
• ImageID: the image this mask lives in.
• LabelName: the MID of the object class this mask belongs to.
• BoxID: an identifier for the box within the image.
• BoxXMin, BoxXMax, BoxYMin, BoxYMax: coordinates of the box linked to the mask, in normalized image coordinates. Note that this is not the bounding box of the mask, but the starting box from which the mask was annotated. These coordinates can be used to relate the mask data with the boxes data.
• PredictedIoU: if present, indicates a predicted IoU value with respect to ground-truth. This quality estimate is machine-generated based on human annotator behaviour. See [3] for details.
• Clicks: if present, indicates the human annotator clicks, which provided guidance during the annotation process we carried out (See [3] for details). This field is encoded using the following format: X1 Y1 T1;X2 Y2 T2;X3 Y3 T3;.... Xi Yi are the coordinates of the click in normalized image coordinates. Ti is the click type, value 0 indicates the annotator marks the point as background, value 1 as part of the object instance (foreground). These clicks can be interesting for researchers in the field of interactive segmentation. They are not necessary for users interested in the final masks only.

Visual relationships

Each row in the file corresponds to a single annotation.

ImageID,LabelName1,LabelName2,XMin1,XMax1,YMin1,YMax1,XMin2,XMax2,YMin2,YMax2,RelationLabel
0009fde62ded08a6,/m/0342h,/m/01d380,0.2682927,0.78549093,0.4977778,0.8288889,0.2682927,0.78549093,0.4977778,0.8288889,is
00198353ef684011,/m/01mzpv,/m/04bcr3,0.23779725,0.30162704,0.6500938,0.7335835,0,0.5819775,0.6482176,0.99906194,at
001e341dd7456c72,/m/04yx4,/m/01mzpv,0.07009346,0.2859813,0.2332708,0.5203252,0.14018692,0.31588784,0.32082552,0.48405254,on
001e341dd7456c72,/m/04yx4,/m/01mzpv,0,0.28317758,0.26454034,0.5540963,0.2224299,0.3411215,0.3908693,0.4859287,on
001e341dd7456c72,/m/01599,/m/04bcr3,0.5551402,0.6084112,0.50343966,0.5490932,0.5411215,0.95981306,0.5090682,0.78361475,on
001e341dd7456c72,/m/04bcr3,/m/01d380,0.7392523,0.9990654,0.3889931,0.518449,0.7392523,0.9990654,0.3889931,0.518449,is
...

• ImageID: the image this relationship instance lives in.
• LabelName1: the label of the first object in the relationship triplet.
• XMin1,XMax1,YMin1,YMax1: normalized bounding box coordinates of the bounding box of the first object.
• LabelName2: the label of the second object in the relationship triplet, or an attribute.
• XMin2, XMax2, YMin2, YMax2: If the relationship is between a pair of objects: normalized bounding box coordinates of the bounding box of the second object. For an object-attribute relationship (RelationLabel="is"): normalized bounding box of the first object (repeated). In this case, LabelName2 is an attribute.
• RelationLabel: the label of the relationship ("is" in case of attributes).

Image Labels

Human-verified and machine-generated image-level labels:

ImageID,Source,LabelName,Confidence
000026e7ee790996,verification,/m/04hgtk,0
000026e7ee790996,verification,/m/07j7r,1
000026e7ee790996,crowdsource-verification,/m/01bqvp,1
000026e7ee790996,crowdsource-verification,/m/0csby,1
000026e7ee790996,verification,/m/01_m7,0
000026e7ee790996,verification,/m/01cbzq,1
000026e7ee790996,verification,/m/01czv3,0
000026e7ee790996,verification,/m/01v4jb,0
000026e7ee790996,verification,/m/03d1rd,0
...

Source: indicates how the annotation was created:

• verification are labels verified by in-house annotators at Google.
• crowdsource-verification are labels verified from the Crowdsource app.
• machine are machine-generated labels.

Confidence: Labels that are human-verified to be present in an image have confidence = 1 (positive labels). Labels that are human-verified to be absent from an image have confidence = 0 (negative labels). Machine-generated labels have fractional confidences, generally >= 0.5. The higher the confidence, the smaller the chance for the label to be a false positive.

Class Names

The class names in MID format can be converted to their short descriptions by looking into class-descriptions.csv:

...
/m/0pc9,Alphorn
/m/0pckp,Robin
/m/0pcm_,Larch
/m/0pcq81q,Soccer player
/m/0pcr,Alpaca
/m/0pcvyk2,Nem
/m/0pd7,Army
/m/0pdnd2t,Bengal clockvine
/m/0pdnpc9,Bushwacker
/m/0pdnsdx,Enduro
/m/0pdnymj,Gekkonidae
...

Note the presence of characters like commas and quotes. The file follows standard CSV escaping rules. e.g.:

/m/02wvth,"Fiat 500 ""topolino"""
/m/03gtp5,Lamb's quarters
/m/03hgsf0,"Lemon, lime and bitters"

Image IDs

It has image URLs, their OpenImages IDs, the rotation information, titles, authors, and license information:

ImageID,Subset,OriginalURL,OriginalLandingURL,License,AuthorProfileURL,Author,Title,
OriginalSize,OriginalMD5,Thumbnail300KURL,Rotation
...
000060e3121c7305,train,https://c1.staticflickr.com/5/4129/5215831864_46f356962f_o.jpg,\
https://www.flickr.com/photos/brokentaco/5215831864,\
https://creativecommons.org/licenses/by/2.0/,\
"https://www.flickr.com/people/brokentaco/","David","28 Nov 2010 Our new house."\
211079,0Sad+xMj2ttXM1U8meEJ0A==,https://c1.staticflickr.com/5/4129/5215831864_ee4e8c6535_z.jpg,0
...

Each image has a unique 64-bit ID assigned. In the CSV files they appear as zero-padded hex integers, such as 000060e3121c7305.

The data is as it appears on the destination websites.

• OriginalSize is the download size of the original image.
• OriginalMD5 is base64-encoded binary MD5, as described here.
• Thumbnail300KURL is an optional URL to a thumbnail with ~300K pixels (~640x480). It is provided for the convenience of downloading the data in the absence of more convenient ways to get the images. If missing, OriginalURL must be used (and then resized to the same size, if needed). These thumbnails are generated on the fly and their contents and even resolution might be different every day.
• Rotation is the number of degrees that the image should be rotated counterclockwise to match the Flickr user intended orientation (0, 90, 180, 270). nan means that this information is not available. Check this announcement for more information about the issue.

Hierarchy for 600 boxable classes

View the set of boxable classes as a hierarchy here or download it as a JSON file:

References

1. "Extreme clicking for efficient object annotation", Papadopolous et al., ICCV 2017.

2. "We don't need no bounding-boxes: Training object class detectors using only human verification, Papadopolous et al., CVPR 2016.

3. "Large-scale interactive object segmentation with human annotators", Benenson et al., CVPR 2019.