Watermark
Last Updated：2020-10-26
Overview
This article describes how to set the watermark. Photo watermark refers to insert another photo or text above the photo as a watermark, which is a means of digital information protection. Currently, the BOS photo processing V1.0 protocol supports two watermarking methods: photo watermarking and text watermarking. BOS divides your original photo into 9 areas as shown in the figure below, and number them according to the position of the photo. Each area contains anchor points.
If required to determine the final position of the watermark on the original photo, you need to determine the following two factors:
- Position of the anchor;
- Designate the distance in the horizontal and vertical directions based on the location of anchor.
The anchor position is as shown in the figure:
Watermark Parameters of Photos
| Parameter name | Resizing command | Type | Value range | Request description | Default value | Is it required |
|---|---|---|---|---|---|---|
| watermark | wm | unsigned | 0,1,2 | Designate the method of making watermark. wm_0 means the watermark feature is disabled; wm_1 means photo watermark; wm_2 means text watermark. |
- | Yes |
| key | k | string | - | Designate the Object name of the watermark photo stored on BOS, that is, ObjectKey. If the Object is stored in a folder, you need to include the folder path. This is required to be the value after Base64 encoding. |
- | Yes |
| gravity | g | unsigned int | 1~9 | Designate the anchor location for the watermark. Please refer to [command of photo watermark](#Command of Photo Watermark) for the meaning of photo anchor. |
9 | No |
| gravityX | x | int | -4096~4096 | Designate the horizontal distance of the watermark based on the anchor. | 10 | No |
| gravityY | y | int | -4096~4096 | Designate the vertical distance of the watermark based on the anchor. | 10 | No |
| angle | a | int | -360~360 | Designate the rotation angle of the the photo with watermark. The positive number indicates clockwise rotation, such as a_60; while the negative number indicates counterclockwise rotation, such as a_-30. |
0 | No |
| opacity | o | unsigned int | 1~100 | Designate the transparency of the the photo with watermark. When the value is 100, it means that the transparency of that of the original photo is the same. |
100 | No |
Note
- The photo with watermark and the original photo should be stored in the same Bucket of BOS.
Parameters of Text Watermark
| Parameter name | Resizing command | Type | Value range | Request description | Default value | Is it required |
|---|---|---|---|---|---|---|
| watermark | wm | unsigned | 0,1,2 | Designate the method of making watermark. wm_0 means the watermark feature is disabled; wm_1 means photo watermark; wm_2 means text watermark. |
- | Yes |
| text | t | string | - | The text watermark needs to be encoded with Base64, and the maximum number of characters after encoding should be no more than 80. |
- | Yes |
| gravity | g | unsigned int |
1~9 | Designate the anchor location for the watermark. Please refer to [command of photo watermark](#Command of Photo Watermark) for the meaning of photo anchor. |
9 | No |
| gravityX | x | int | -4096~4096 | Designate the distance of horizontal distance of the watermark based on the anchor. |
10 | No |
| gravityY | y | int | -4096~4096 | Designate the distance of vertical distance of the watermark based on the anchor. |
10 | No |
| angle | a | int | -360~360 | Designate the rotation angle of the the photo with watermark. The positive number indicates clockwise rotation, such as a_60; while the negative number indicates counterclockwise rotation, such as a_-30. |
0 | No |
| fontSize | sz | unsigned int |
1~1024 | Designate the font size of watermark, which is in px. |
30 | No |
| fontColor | fc | string | - | Designate the font color as an 8-bit hexadecimal string, where every 2 bits are used to represent an item in RGBA. The first six bits represent RGB color respectively, such as ffffff; while the last two bits represent the Alpha channel, which can be omitted, and when omitted, it refers to opaque. E.g.: 000000ff refers to the black opaque font. |
000000 | No |
| fontFamily | ff | string | - | Designate the font type of the font, select the value , and conduct Base64 encoding. See the list below for supported font types. |
Song typeface | No |
| fontStyle | fs | string | normal( Conventional) italic( Italic) bold( Bold) |
Designate the font style. | normal | No |
The supported font types:
| Parameter value | Font type |
|---|---|
| MicrosoftYaHei | Microsoft YaHei |
| FangSong | Imitation Song-Dynasty-style typeface |
| SimHei | Blackbody |
| KaiTi | Regular script |
| SimSun | Song typeface |
| FZBeiWeiKaiShuJianTi | Founder simplified regular script of the Northern Wei Dynasty |
| FZBoYaSongJianTi | Founder simplified Song-Dynasty-style typeface |
| FZCuHeiSongJianTi | Founder simplified Song-Dynasty-style bold black |
| FZLanTingZhongHeiJianTi | Founder Lanting simplified black typeface |
| FZZhengHei | Founder JhengHei |
| AvantGarde | AvantGarde |
| Bookman | Bookman |
| Courier | Courier |
| Helvetica | Helvetica |
| HelveticaNarrow | HelveticaNarrow |
| NewCenturySchlbk | NewCenturySchlbk |
| Palatino | Palatino |
| Times | Times |
| Symbol | Symbol |
Note
- Text effects are rendered only if the fontfamily supports the FontStyle effect.
- If the specified font style is not included in the currently supported fontfamily list, the default font should be Song typeface.
The Mixed Photo and Text Watermark
The mixed photo and text watermark refers to print the photo watermark and text watermark on the original photo at the same time. Since the photo watermark and text watermark are two independent commands, the mixed photo and text watermark needs to be implemented by pipeline.
Example
Photo watermark example
The original photo is image.jpg, and the photo with watermark is bce-documentation/BOS/bce.jpg (Base64 is encoded as “YmNlLWRvY3VtZW50YXRpb24vQk9TL2JjZS5qcGc=”).
- Add the photo watermark in the lower right corner, and designate the vertical distance of 10 and the transparency of 60.
- Add the watermark in the lower left corner, determine the default values as horizontal and vertical distances, specify the transparency of 50, and rotate 90 degrees clockwise.
Text watermark example
- The text watermark is the simplest, and the text content is “hello world”.
https://doc.bce.baidu.com/bce-documentation/BOS/image.jpg@wm_2,t_aGVsbG8gd29ybGQ=
- The text content is “hello world”, the font type is Microsoft YaHei, the font color and font size are defaulted, the font style is bold, the watermark position is in the middle right, the horizontal distance from the anchor point is 20, the vertical distance is 20, and the clockwise rotation is 30 degrees.
The mixed photo and text watermark
- The simplest mixed photo and text watermark The photo is in the form of bce-documentation/BOS/bce.jpg, the text content is “hello world”, and the other parameters are all default value.
- The mixed photo and text watermark The watermark photo is in the form of bce-documentation/BOS/bce.jpg, which is located at the lower left corner of the original photo with the horizontal distance from the anchor point of 15, the vertical distance of 20, and the transparency of 50; the text content is “hello world”, which is located at the top with the vertical distance of 100, and the font color is lavender.
