Dynamic Programming
Dynamic programming is a programming method that stores the results of sub-calculations in order to simplify calculating a more complex result. Dynamic programming is used in seam carving for computing seams.
If attempting to compute a vertical seam (path) of lowest energy, for each pixel in a row we compute the energy of the current pixel plus the energy of one of the three possible pixels above it.
This is better described by this image:
The first row has no rows above it, so the sum (black) is just the energy value of the current pixel (red).
The second row, if we look at the second pixel for example, we see its energy value is 2 (red). If we look above it, it has a choice of either 1, 4, or 3 (black). Since 1 is the minimum number of the three values, we ignore the other two and set the sum of the pixel to its energy value which is 2 (red) plus 1 (black).
After the above operation is carried out for every pixel in the second row, we go to the third row:
We repeat the process in row two in row three to end up with the final cumultive sums for the seams/paths. The lowest value or values are the seams with the lowest energy, which would be in this example the seams with '5' in the last row.
To trace the seam/path, work from the last row and follow the green arrows:
Read more about this topic: Seam Carving, Seams, Computing Seams
Famous quotes containing the words dynamic and/or programming:
“Knowledge about life is one thing; effective occupation of a place in life, with its dynamic currents passing through your being, is another.”
—William James (1842–1910)
“If there is a price to pay for the privilege of spending the early years of child rearing in the driver’s seat, it is our reluctance, our inability, to tolerate being demoted to the backseat. Spurred by our success in programming our children during the preschool years, we may find it difficult to forgo in later states the level of control that once afforded us so much satisfaction.”
—Melinda M. Marshall (20th century)