There probably aren't any perfectly humane farms in the real world (Michael Pollan's book The Omnivore's Dilemma provides proof of that), but I think there are some that come close.
The chickens in the first picture lived on an organic farm in Hawaii that I stayed at last summer. The chickens in the second picture lived in the English Lake District. It's reasonable to think these animals had lives that were 99.9% pleasant. The problems remaining in their lives were two: (1) At some point they were going to be eaten for dinner and the killing was likely to be painful (though quick). And (2) throughout their lives they were being used as resources. The eggs they labored to produce were taken from them, though in return they were housed and fed.
Is there a problem with (1) and (2)? I just want to make a "meta" point and not answer the question. The "meta" point is that this is a difficult question. There are really difficult and perplexing problems here. As the saying goes: reasonable people will disagree. I think that's what Peter Singer must have been thinking when he wrote, "I can respect conscientious people who take care to eat only meat that comes from such animals," in the last chapter of Animal Liberation, even though in chapter 4 he had already made many arguments that people ought to give up eating chicken--including "humane chicken."
The questions about (1) and (2) are difficult. Even those who say "wrong" and "wrong" can just have a flickering sense of wrongness, not a sense durable enough to survive the competition with their fondness for chicken and eggs. At the same time, I find that almost everyone sees a problem with what is being done to the third chicken--her life is being made a living hell. And that's the fate of almost all of the 6 million chickens we kill for food in the US, every six hours.
To save that chicken from a miserable life, many people are prepared to act differently. Maybe they'll pay a little more for cage-free or free-range eggs (which are better if not perfect), or go to the polls to vote for a referendum, Some will stop eating chicken altogether, or stop eating both chicken and eggs.
Because of the difficulty of (1) and (2), I don't think the main thrust of animal advocacy should be eliminating the whole practice of using animals for food. I'm (honestly) pessimistic about that campaign, but optimistic about the campaign to alleviate suffering. Since it matters enormously whether animals suffer, whether or not there's also a problem with (1) and (2), I think that's a rational way to set priorities.
Just for fun: more happy animals, for your viewing pleasure. The pig lives in Central Pennsylvania. The sheep were grazing on a hill very near Hadrian's wall in northern England.
UPDATE: Maybe I didn't make this clear. We cannot possibly make every farm animal as happy as a Hawaiian chicken or the pig and the sheep in these pictures. To achieve much less suffering, there has to be at least a reduction of the number of animals eaten. But suffering should be the main focus of arguments for veganism and vegetarianism, because (1) and (2) just aren't compelling enough to most people or even to most conscientious and clear-thinking philosophers. I say this after many years of watching lots of people react to animal ethics messages.