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Of course, there are many complex interactions that take place between the collection of light in the retina and the higher brain processing that takes place in the visual cortex. In fact, the first step in this process is a severe compression of simulus information:
The picture above shows the light receptive cones and rods on the far left. The stimulated receptors pass information down a series of intermediary cells within the retina including the retinal ganglion cells on the far right. There are roughly 125 million receptors in the retina, but only one million retinal ganglion cells. This relationship ensures a compression ratio of at least 125 : 1 occuring within the retina, well before any information reaches the brain.
The important lesson to take away from this exercise is the following: What you see is not what you get. In other words, the "image" of the world received by light receptors in your eye is not exactly the same as the "image" that reaches your brain. Over the course of billions of years of evolution, the human visual system has acquired countless intermediary stages that assist in the creation of the final visual perception we experience.