cv2 imdecode returns none with base64 string
-1
When i try to convert base64 string into image i am getting none in CV2.
Following is my code
import cv2
import numpy as np
def bsae62toimage(imgvalue):
imge = "R0lGODlhEAAQAMQAAORHHOVSKudfOulrSOp3WOyDZu6QdvCchPGolfO0o/XBs/fNwfjZ0frl3/zy7////wAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACH5BAkAABAALAAAAAAQABAAAAVVICSOZGlCQAosJ6mu7fiyZeKqNKToQGDsM8hBADgUXoGAiqhSvp5QAnQKGIgUhwFUYLCVDFCrKUE1lBavAViFIDlTImbKC5Gm2hB0SlBCBMQiB0UjIQA7"
nparr = np.fromstring(imge,np.uint8)
print(nparr.shape)
img1 = cv2.imdecode(nparr,cv2.IMREAD_UNCHANGED)
print(img1.shape)
It is printing the numpy array but cv2.imdecode is returning None. Can you help me to find the problem in my code?
My Findings: np.fromstring it returns 1D array. I assume it should it should return 3D array. But i may be wrong.
linux python-3.x opencv base64 cv2
asked Nov 26 '18 at 5:22
BacktrackBacktrack
5,60533580
add a comment |
-1
When i try to convert base64 string into image i am getting none in CV2.
Following is my code
import cv2
import numpy as np
def bsae62toimage(imgvalue):
imge = "R0lGODlhEAAQAMQAAORHHOVSKudfOulrSOp3WOyDZu6QdvCchPGolfO0o/XBs/fNwfjZ0frl3/zy7////wAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACH5BAkAABAALAAAAAAQABAAAAVVICSOZGlCQAosJ6mu7fiyZeKqNKToQGDsM8hBADgUXoGAiqhSvp5QAnQKGIgUhwFUYLCVDFCrKUE1lBavAViFIDlTImbKC5Gm2hB0SlBCBMQiB0UjIQA7"
nparr = np.fromstring(imge,np.uint8)
print(nparr.shape)
img1 = cv2.imdecode(nparr,cv2.IMREAD_UNCHANGED)
print(img1.shape)
It is printing the numpy array but cv2.imdecode is returning None. Can you help me to find the problem in my code?
My Findings: np.fromstring it returns 1D array. I assume it should it should return 3D array. But i may be wrong.
linux python-3.x opencv base64 cv2
asked Nov 26 '18 at 5:22
BacktrackBacktrack
5,60533580
dear downvoters - leave your valuable comments
– Backtrack
Nov 26 '18 at 8:16
add a comment |
-1
-1
-1
When i try to convert base64 string into image i am getting none in CV2.
Following is my code
import cv2
import numpy as np
def bsae62toimage(imgvalue):
imge = "R0lGODlhEAAQAMQAAORHHOVSKudfOulrSOp3WOyDZu6QdvCchPGolfO0o/XBs/fNwfjZ0frl3/zy7////wAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACH5BAkAABAALAAAAAAQABAAAAVVICSOZGlCQAosJ6mu7fiyZeKqNKToQGDsM8hBADgUXoGAiqhSvp5QAnQKGIgUhwFUYLCVDFCrKUE1lBavAViFIDlTImbKC5Gm2hB0SlBCBMQiB0UjIQA7"
nparr = np.fromstring(imge,np.uint8)
print(nparr.shape)
img1 = cv2.imdecode(nparr,cv2.IMREAD_UNCHANGED)
print(img1.shape)
It is printing the numpy array but cv2.imdecode is returning None. Can you help me to find the problem in my code?
My Findings: np.fromstring it returns 1D array. I assume it should it should return 3D array. But i may be wrong.
linux python-3.x opencv base64 cv2
asked Nov 26 '18 at 5:22
BacktrackBacktrack
5,60533580
When i try to convert base64 string into image i am getting none in CV2.
Following is my code
import cv2
import numpy as np
def bsae62toimage(imgvalue):
imge = "R0lGODlhEAAQAMQAAORHHOVSKudfOulrSOp3WOyDZu6QdvCchPGolfO0o/XBs/fNwfjZ0frl3/zy7////wAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACH5BAkAABAALAAAAAAQABAAAAVVICSOZGlCQAosJ6mu7fiyZeKqNKToQGDsM8hBADgUXoGAiqhSvp5QAnQKGIgUhwFUYLCVDFCrKUE1lBavAViFIDlTImbKC5Gm2hB0SlBCBMQiB0UjIQA7"
nparr = np.fromstring(imge,np.uint8)
print(nparr.shape)
img1 = cv2.imdecode(nparr,cv2.IMREAD_UNCHANGED)
print(img1.shape)
It is printing the numpy array but cv2.imdecode is returning None. Can you help me to find the problem in my code?
My Findings: np.fromstring it returns 1D array. I assume it should it should return 3D array. But i may be wrong.
linux python-3.x opencv base64 cv2
linux python-3.x opencv base64 cv2
asked Nov 26 '18 at 5:22
BacktrackBacktrack
5,60533580
asked Nov 26 '18 at 5:22
BacktrackBacktrack
5,60533580
asked Nov 26 '18 at 5:22
BacktrackBacktrack
5,60533580
asked Nov 26 '18 at 5:22
BacktrackBacktrack
5,60533580
asked Nov 26 '18 at 5:22
BacktrackBacktrack
5,60533580
5,60533580
dear downvoters - leave your valuable comments
– Backtrack
Nov 26 '18 at 8:16
add a comment |
dear downvoters - leave your valuable comments
– Backtrack
Nov 26 '18 at 8:16
dear downvoters - leave your valuable comments
– Backtrack
Nov 26 '18 at 8:16
dear downvoters - leave your valuable comments
– Backtrack
Nov 26 '18 at 8:16
add a comment |
1 Answer
1
active
oldest
votes
0
Since it is unclear as from where have you obtained the imge = "R0lGODlhEA..." variable. I would present an ideal flow for converting OpenCV image to base64 string and converting it back to OpenCV img as:
import cv2
import base64
import numpy as np
def to_base64(img):
_, buf = cv2.imencode(".png", img)
return base64.b64encode(buf)
def from_base64(buf):
buf_decode = base64.b64decode(buf)
buf_arr = np.fromstring(buf_decode, dtype=np.uint8)
return cv2.imdecode(buf_arr, cv2.IMREAD_UNCHANGED)
img = cv2.imread("/path/to/img.png")
img_base64 = to_base64(img)
img_decoded = from_base64(img_base64)
print img_decoded.shape
Also the documentation states that:
If the buffer is too short or contains invalid data, the empty
matrix/image is returned.
It seems to me that imge = "R0lGODlhEA..." is invalid.
answered Nov 26 '18 at 6:53
ZdaRZdaR
13.4k33554
I am getting this string from JAVA. I am trying to integrate the model written in Tensorflow into the JAVA application. The JAVA application emits the image into base64 string
– Backtrack
Nov 26 '18 at 8:14
I think you should read the Java method documentation carefully and compare the results of Python and Java on same image, to see if base64 encoded data is consistent on both sides for a smaller image say 10x10. Also share the Java code for base64 conversion if possible
– ZdaR
Nov 26 '18 at 8:22
So, What i am doing is - I render a webpage using selenium and take the screenshot using following code - String imagecontent = null; if(screenshotenabled){ imagecontent = driver.getScreenshotAs(OutputType.BASE64); }
– Backtrack
Nov 26 '18 at 8:25
Also in the code you have given i made a small change - def to_base64(filepath): with open(filepath, "rb") as imageFile: bstr = base64.b64encode(imageFile.read()) return bstr when i run the script with this change it is giving me wrong size : (2184, 1280, 4).
– Backtrack
Nov 26 '18 at 8:32
add a comment |
Your Answer
StackExchange.ifUsing("editor", function () {
StackExchange.using("externalEditor", function () {
StackExchange.using("snippets", function () {
StackExchange.snippets.init();
});
});
}, "code-snippets");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
draft saved
draft discarded
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53475135%2fcv2-imdecode-returns-none-with-base64-string%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
0
Since it is unclear as from where have you obtained the imge = "R0lGODlhEA..." variable. I would present an ideal flow for converting OpenCV image to base64 string and converting it back to OpenCV img as:
import cv2
import base64
import numpy as np
def to_base64(img):
_, buf = cv2.imencode(".png", img)
return base64.b64encode(buf)
def from_base64(buf):
buf_decode = base64.b64decode(buf)
buf_arr = np.fromstring(buf_decode, dtype=np.uint8)
return cv2.imdecode(buf_arr, cv2.IMREAD_UNCHANGED)
img = cv2.imread("/path/to/img.png")
img_base64 = to_base64(img)
img_decoded = from_base64(img_base64)
print img_decoded.shape
Also the documentation states that:
If the buffer is too short or contains invalid data, the empty
matrix/image is returned.
It seems to me that imge = "R0lGODlhEA..." is invalid.
answered Nov 26 '18 at 6:53
ZdaRZdaR
13.4k33554
I am getting this string from JAVA. I am trying to integrate the model written in Tensorflow into the JAVA application. The JAVA application emits the image into base64 string
– Backtrack
Nov 26 '18 at 8:14
I think you should read the Java method documentation carefully and compare the results of Python and Java on same image, to see if base64 encoded data is consistent on both sides for a smaller image say 10x10. Also share the Java code for base64 conversion if possible
– ZdaR
Nov 26 '18 at 8:22
So, What i am doing is - I render a webpage using selenium and take the screenshot using following code - String imagecontent = null; if(screenshotenabled){ imagecontent = driver.getScreenshotAs(OutputType.BASE64); }
– Backtrack
Nov 26 '18 at 8:25
Also in the code you have given i made a small change - def to_base64(filepath): with open(filepath, "rb") as imageFile: bstr = base64.b64encode(imageFile.read()) return bstr when i run the script with this change it is giving me wrong size : (2184, 1280, 4).
– Backtrack
Nov 26 '18 at 8:32
add a comment |
0
Since it is unclear as from where have you obtained the imge = "R0lGODlhEA..." variable. I would present an ideal flow for converting OpenCV image to base64 string and converting it back to OpenCV img as:
import cv2
import base64
import numpy as np
def to_base64(img):
_, buf = cv2.imencode(".png", img)
return base64.b64encode(buf)
def from_base64(buf):
buf_decode = base64.b64decode(buf)
buf_arr = np.fromstring(buf_decode, dtype=np.uint8)
return cv2.imdecode(buf_arr, cv2.IMREAD_UNCHANGED)
img = cv2.imread("/path/to/img.png")
img_base64 = to_base64(img)
img_decoded = from_base64(img_base64)
print img_decoded.shape
Also the documentation states that:
If the buffer is too short or contains invalid data, the empty
matrix/image is returned.
It seems to me that imge = "R0lGODlhEA..." is invalid.
answered Nov 26 '18 at 6:53
ZdaRZdaR
13.4k33554
I am getting this string from JAVA. I am trying to integrate the model written in Tensorflow into the JAVA application. The JAVA application emits the image into base64 string
– Backtrack
Nov 26 '18 at 8:14
I think you should read the Java method documentation carefully and compare the results of Python and Java on same image, to see if base64 encoded data is consistent on both sides for a smaller image say 10x10. Also share the Java code for base64 conversion if possible
– ZdaR
Nov 26 '18 at 8:22
So, What i am doing is - I render a webpage using selenium and take the screenshot using following code - String imagecontent = null; if(screenshotenabled){ imagecontent = driver.getScreenshotAs(OutputType.BASE64); }
– Backtrack
Nov 26 '18 at 8:25
Also in the code you have given i made a small change - def to_base64(filepath): with open(filepath, "rb") as imageFile: bstr = base64.b64encode(imageFile.read()) return bstr when i run the script with this change it is giving me wrong size : (2184, 1280, 4).
– Backtrack
Nov 26 '18 at 8:32
add a comment |
0
0
0
Since it is unclear as from where have you obtained the imge = "R0lGODlhEA..." variable. I would present an ideal flow for converting OpenCV image to base64 string and converting it back to OpenCV img as:
import cv2
import base64
import numpy as np
def to_base64(img):
_, buf = cv2.imencode(".png", img)
return base64.b64encode(buf)
def from_base64(buf):
buf_decode = base64.b64decode(buf)
buf_arr = np.fromstring(buf_decode, dtype=np.uint8)
return cv2.imdecode(buf_arr, cv2.IMREAD_UNCHANGED)
img = cv2.imread("/path/to/img.png")
img_base64 = to_base64(img)
img_decoded = from_base64(img_base64)
print img_decoded.shape
Also the documentation states that:
If the buffer is too short or contains invalid data, the empty
matrix/image is returned.
It seems to me that imge = "R0lGODlhEA..." is invalid.
answered Nov 26 '18 at 6:53
ZdaRZdaR
13.4k33554
Since it is unclear as from where have you obtained the imge = "R0lGODlhEA..." variable. I would present an ideal flow for converting OpenCV image to base64 string and converting it back to OpenCV img as:
import cv2
import base64
import numpy as np
def to_base64(img):
_, buf = cv2.imencode(".png", img)
return base64.b64encode(buf)
def from_base64(buf):
buf_decode = base64.b64decode(buf)
buf_arr = np.fromstring(buf_decode, dtype=np.uint8)
return cv2.imdecode(buf_arr, cv2.IMREAD_UNCHANGED)
img = cv2.imread("/path/to/img.png")
img_base64 = to_base64(img)
img_decoded = from_base64(img_base64)
print img_decoded.shape
Also the documentation states that:
If the buffer is too short or contains invalid data, the empty
matrix/image is returned.
It seems to me that imge = "R0lGODlhEA..." is invalid.
answered Nov 26 '18 at 6:53
ZdaRZdaR
13.4k33554
answered Nov 26 '18 at 6:53
ZdaRZdaR
13.4k33554
answered Nov 26 '18 at 6:53
ZdaRZdaR
13.4k33554
answered Nov 26 '18 at 6:53
ZdaRZdaR
13.4k33554
13.4k33554
I am getting this string from JAVA. I am trying to integrate the model written in Tensorflow into the JAVA application. The JAVA application emits the image into base64 string
– Backtrack
Nov 26 '18 at 8:14
I think you should read the Java method documentation carefully and compare the results of Python and Java on same image, to see if base64 encoded data is consistent on both sides for a smaller image say 10x10. Also share the Java code for base64 conversion if possible
– ZdaR
Nov 26 '18 at 8:22
So, What i am doing is - I render a webpage using selenium and take the screenshot using following code - String imagecontent = null; if(screenshotenabled){ imagecontent = driver.getScreenshotAs(OutputType.BASE64); }
– Backtrack
Nov 26 '18 at 8:25
Also in the code you have given i made a small change - def to_base64(filepath): with open(filepath, "rb") as imageFile: bstr = base64.b64encode(imageFile.read()) return bstr when i run the script with this change it is giving me wrong size : (2184, 1280, 4).
– Backtrack
Nov 26 '18 at 8:32
add a comment |
I am getting this string from JAVA. I am trying to integrate the model written in Tensorflow into the JAVA application. The JAVA application emits the image into base64 string
– Backtrack
Nov 26 '18 at 8:14
I think you should read the Java method documentation carefully and compare the results of Python and Java on same image, to see if base64 encoded data is consistent on both sides for a smaller image say 10x10. Also share the Java code for base64 conversion if possible
– ZdaR
Nov 26 '18 at 8:22
So, What i am doing is - I render a webpage using selenium and take the screenshot using following code - String imagecontent = null; if(screenshotenabled){ imagecontent = driver.getScreenshotAs(OutputType.BASE64); }
– Backtrack
Nov 26 '18 at 8:25
Also in the code you have given i made a small change - def to_base64(filepath): with open(filepath, "rb") as imageFile: bstr = base64.b64encode(imageFile.read()) return bstr when i run the script with this change it is giving me wrong size : (2184, 1280, 4).
– Backtrack
Nov 26 '18 at 8:32
I am getting this string from JAVA. I am trying to integrate the model written in Tensorflow into the JAVA application. The JAVA application emits the image into base64 string
– Backtrack
Nov 26 '18 at 8:14
I am getting this string from JAVA. I am trying to integrate the model written in Tensorflow into the JAVA application. The JAVA application emits the image into base64 string
– Backtrack
Nov 26 '18 at 8:14
I think you should read the Java method documentation carefully and compare the results of Python and Java on same image, to see if base64 encoded data is consistent on both sides for a smaller image say 10x10. Also share the Java code for base64 conversion if possible
– ZdaR
Nov 26 '18 at 8:22
I think you should read the Java method documentation carefully and compare the results of Python and Java on same image, to see if base64 encoded data is consistent on both sides for a smaller image say 10x10. Also share the Java code for base64 conversion if possible
– ZdaR
Nov 26 '18 at 8:22
So, What i am doing is - I render a webpage using selenium and take the screenshot using following code - String imagecontent = null; if(screenshotenabled){ imagecontent = driver.getScreenshotAs(OutputType.BASE64); }
– Backtrack
Nov 26 '18 at 8:25
So, What i am doing is - I render a webpage using selenium and take the screenshot using following code - String imagecontent = null; if(screenshotenabled){ imagecontent = driver.getScreenshotAs(OutputType.BASE64); }
– Backtrack
Nov 26 '18 at 8:25
Also in the code you have given i made a small change - def to_base64(filepath): with open(filepath, "rb") as imageFile: bstr = base64.b64encode(imageFile.read()) return bstr when i run the script with this change it is giving me wrong size : (2184, 1280, 4).
– Backtrack
Nov 26 '18 at 8:32
Also in the code you have given i made a small change - def to_base64(filepath): with open(filepath, "rb") as imageFile: bstr = base64.b64encode(imageFile.read()) return bstr when i run the script with this change it is giving me wrong size : (2184, 1280, 4).
– Backtrack
Nov 26 '18 at 8:32
add a comment |
draft saved
draft discarded
Thanks for contributing an answer to Stack Overflow!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
draft saved
draft discarded
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53475135%2fcv2-imdecode-returns-none-with-base64-string%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
dear downvoters - leave your valuable comments
– Backtrack
Nov 26 '18 at 8:16