| 108 | |
| 109 | class RandomMultipleGallerySamplerNoCam(Sampler): |
| 110 | def __init__(self, data_source, num_instances=4): |
| 111 | super().__init__(data_source) |
| 112 | |
| 113 | self.data_source = data_source |
| 114 | self.index_pid = defaultdict(int) |
| 115 | self.pid_index = defaultdict(list) |
| 116 | self.num_instances = num_instances |
| 117 | |
| 118 | for index, _item in enumerate(data_source): |
| 119 | pid = _item[1] |
| 120 | # (_, pid, cam) |
| 121 | if pid < 0: |
| 122 | continue |
| 123 | self.index_pid[index] = pid |
| 124 | self.pid_index[pid].append(index) |
| 125 | |
| 126 | self.pids = list(self.pid_index.keys()) |
| 127 | self.num_samples = len(self.pids) |
| 128 | |
| 129 | def __len__(self): |
| 130 | return self.num_samples * self.num_instances |