Tag: non-technical features contributing to technical character

Edge Detection – T 0165/ 12 – 6 July 2017

In this decision, the Board found that the description of the main request did not support the claim, as the description disclosed only one specific example of a merely general feature (“first phase congruency component”). In an auxiliary request, the appellant overcame this rejection, but the claimed subject-matter is still considered not to be inventive

Object of the Invention:

  • method for edge detection of an image
  • the method categorises pixels in the image as edge pixels or non-edge pixels

Board I (support by the description – main request):

  • in the application itself, no different way to determine the phase congruency at a pixel is disclosed than to calculate the ratio between the local energy at the pixel and the sum of Fourier components
  • also in the statement of grounds the appellant provided no additional example and, thus, failed to support its view that a different phase congruency component could be used
  • hence, it is a mere allegation that other “first phase congruency components” could be used
  • according to the established jurisprudence of the boards of appeal, the requirement of 84 EPC means that the subject-matter of the claim must be taken from the description and it is not admissible to claim something that is not described
  • in decision T 94/05, in particular, the board pointed out that the requirement for the claims to be supported by the description was intended to ensure that the extent of protection as defined by the patent claims corresponds to the technical contribution of the disclosed invention to the art
  • therefore the claims must reflect the actual contribution to the art in such a way that the skilled person is able to perform the invention in the entire range claimed
  • the skilled person, at least after reading the patent specification, taking account of his common general knowledge, and possibly also after carrying out normal experiments, must actually be provided with at least a plurality of different embodiment variants
  • in the present case, the use of the term “first phase congruence component” leaves it open, what other embodiments besides the “local energy” are envisaged
  • –> there is not enough support in the description for using the broad term “first phase congruency component” in the independent claims instead of the only embodiment disclosed in the specification, i.e. the “local energy”

Board II (inventive step – auxiliary request):

  • technical effect disclosed in the application is: “This allows for pixels that fail the phase congruency test, to be counted as edge pixels if their local energy satisfies the phase congruency component criteria.“
  • a person skilled in the art recognizing that a first method for edge detection does not result in an expected number of edge pixels evidently has three straightforward possibilities to increase the number of edge pixels:
    1. by using another – better – method for edge detection
    2. by adapting the first method for edge detection (for instance by reducing a respective threshold that distinguishes between non-edge pixels and edge pixels)
    3. by using a further known method for edge detection, which provides different results (i.e. additional edge pixels) than the first method and combining the results of both methods
  • for instance, an example for an algorithm using different methods for detecting different kind of edges is disclosed in D3
  • choosing one out of these straightforward possibilities does not involve an inventive step
  • the Board does not see an inventive step in using the local energy method for finding additional edge pixels that were missed by the first method (as claimed) as compared to rejecting edge pixels by using the local energy method that were found by the first method, but should not be considered as edge pixels (as disclosed in D1)
  • this is considered a mere implementation detail, depending on the choice of criteria of the first method, which might cause too many or not enough edge pixels

Image classification / STMICROELECTRONICS – T 1148/05 – 27 May 2009

In this decision, a method of image classification was claimed. The Board assumed that all features contribute to the technical character and that the sufficiency of disclosure was given.

Object of the Invention:

  • image classification method for classifying digital images into photographs, texts, and graphics
  • conventional heuristic methods implemented by expert systems present a number of drawbacks, in particular the computational complexity required for analysing the large number of pixels of an image
  • another problem is touched on by the “impossibility of optimising analysis using parallel architectures”
  • the thrust of the application is for constructing a classification algorithm (“tree-structured classifier”) which is both powerful in terms of class discrimination and efficient in terms of processing speed

Board I (sufficiency of disclosure (Article 83 EPC):

  • examining division has argued that the application does not disclose any specific example of a tree classifier adapted to a specific set of image classes
  • however, the application does disclose the “high-level classification problem” (i.e. to distinguish photographs from graphics and texts, see paragraphs 0002 and 0046) and it discloses that 72 lowlevel features have been chosen (from among 389 features, for example, see paragraphs 0016 and 0052) to carry out the test described in paragraphs 0047 to 0053
  • background of that choice may lack detail but it still provides the general teaching that a (sub-)set of low-level features can be chosen according to general criteria (discrimination power and efficiency, column 3, lines 22 to 25) and managed in any combination (paragraph 0020) to build a classifier fulfilling a set of conditions (see e.g. paragraphs 0021/0022, 0039, 0042)

Board II (inventive step):

  • all features are assumed to contribute to the technical character of the claimed subject matter
  • general aspects of processing and pre-classifying digital images are old
  • however, the claimed method derives novelty from the use of a large library of 22 specific technical image parameters (low-level features) which are not disclosed in combination in any of the available prior art documents
  • Article 56 EPC 1973 asks for an inventive technical contribution (T 641/00-Two identities/COMVIK)
  • the following line of argument guides the skilled person in an obvious manner from the prior art to the claimed method:
    • classification of digital images for the adoption of the most suitable image-processing strategies has become “an indispensable need“, see application
    • according to D2, which may be used as a starting point, Web images are classified into photographs and graphics
    • in digital image processing, it is well-known (and inevitable) to construct a classification algorithm before it is used for classifying images
    • when constructing an algorithm for classifying digital images, it is well-known to accomplish this by way of a tree classifier using features or parameters which describe a digital image, see e.g. the prior art referred to in the application itself
    • invention mainly differs from prior art by the library of specific low-level features for improving the classification result
    • however, it is evident that all the image features which are known to describe properties of digital images are natural candidates for distinguishing images and classes of images, from each other
    • the skilled person has an expectation of improvement in that any low-level feature is prima facie suitable for discriminating image classes at least at a high level.
    • the skilled person designing a binary classification tree obviously prefers features having a great power of discriminating two classes (see e.g. D3, page 4, second paragraph)
    • the application itself presents most of its low-level features as forming part of the prior art
    • regarding the few features for which no prior art has been cited in the application, the application still conveys the impression that those features represent usual parameters for describing and analysing digital images
    • otherwise, if they were fundamentally new to the image processing person, they would have to be disclosed in much greater detail
    • –> no inventive step