Establishing a degree of browning of food to be cooked

Patent metadata

Field	Value
Publication number	US-2019242584-A1
Application number	US-201716320560-A
Country	US
Kind code	A1
Filing date	Aug 1, 2017
Priority date	Aug 18, 2016
Publication date	Aug 8, 2019
Grant date	—

Abstract

In a method for establishing a degree of browning of food to be cooked in a cooking chamber of a household cooking appliance, a reference image is captured by a camera of the household cooking appliance, which camera is directed into the cooking chamber. A first measurement image is captured at a first brightness of a light source of the household cooking appliance, and a second measurement image is captured at a second brightness of the light source. A difference image is generated from the first measurement image and the second measurement image, and the difference image is compared with the reference image.

First claim

1 - 14 . (canceled)

15 . A method for establishing a degree of browning of food to be cooked in a cooking chamber of a household cooking appliance, comprising:
capturing a reference image by a camera of the household cooking appliance, which camera is directed into the cooking chamber; capturing a first measurement image at a first brightness of a light source of the household cooking appliance; capturing a second measurement image at a second brightness of the light source; generating a difference image from the first measurement image and the second measurement image; and comparing the difference image with the reference image.

16 . The method of claim 15 , wherein comparing the difference image with the reference image includes subtracting the reference image from the difference image.

17 . The method of claim 15 , wherein the reference image is a difference image which is generated from a first image captured at the first brightness and a second image captured at the second brightness.

18 . The method of claim 15 , wherein the first brightness is zero and the second brightness corresponds to a brightness when the light source is switched on.

19 . The method of claim 15 , further comprising operating the light source by pulse-width modulation at an eye inertia frequency.

20 . The method of claim 19 , wherein the first measurement image is captured during at least one off-phase of a pulse-width modulation and the second measurement image is captured during at least one on-phase of the pulse-width modulation.

21 . The method of claim 15 , wherein the light source has an LED.

22 . The method of claim 15 , wherein the difference image is compared in at least one area with the reference image.

23 . The method of claim 15 , wherein the difference image is compared with the reference image in an area with the proviso that the area has become darker as a cooking process progresses over time, or that the area is free of a predetermined pattern or that the area has been predetermined by a user.

24 . The method of claim 15 , further comprising triggering an action by the household cooking appliance based on the comparison of the difference image with the reference image.

25 . The method of claim 15 , wherein comparing he difference image with the reference image comprises a determination of whether a result of the comparison fulfills a predetermined criterion.

26 . The method of claim 25 , wherein the result of the comparison comprises reaching a predetermined proportion of pixels with a minimum coloration.

27 . The method of claim 15 , further comprising compensating a reduction in a brightness of the light source due to ageing.

28 . A household cooking appliance, comprising:
a camera directed into a cooking chamber; a light source configured to illuminate the cooking chamber; and a control device coupled to the camera and the light source, said household cooking appliance being configured to:
capture a reference image by the camera,
capture a first measurement image at a first brightness of the light source,
capture a second measurement image at a second brightness of the light source,
generate a difference image from the first measurement image and the second measurement image, and
compare the difference image with the reference image.

Assignees

• Bsh Hausgeraete Gmbh

Inventors

• Ebert Sandra
• Schleser Roland

Classifications

• A23V2002/00

  Food compositions, function of food ingredients or processes for food or foodstuffs · CPC title

• A47J37/085

  with means for sensing the bread condition · CPC title

• F24C7/085 Primary

  on baking ovens · CPC title

• A23L5/10

  General methods of cooking foods, e.g. by roasting or frying · CPC title

• F24C7/08 Primary

  Arrangement or mounting of control or safety devices · CPC title