rendering code

Author: chrischoy

tools/render_models.py

@@ -0,0 +1,100 @@
+#!/usr/bin/env python3
+
+import _init_paths
+import numpy as np
+import os
+
+from lib.config import cfg
+from lib.data_io import category_model_id_pair, get_model_file
+from multiprocessing import Pool
+
+
+def render_model(category, model_id, viewpoints_num, overwrite=False):
+    from lib.blender_renderer import ShapeNetRenderer
+    """Render a single model using a given renderer."""
+    model_paths = get_model_file(category, model_id)
+    rendering_dir = os.path.join(cfg.DIR.RENDERING_ROOT_PATH, category,
+                                 model_id, cfg.DIR.RENDERING_SUBFOLDER)
+
+    if not os.path.isdir(rendering_dir):
+        os.makedirs(rendering_dir)
+
+    # Rendering results configuration.
+    rendered_img_list = os.path.join(rendering_dir,
+                                     cfg.RENDERING.RENDERED_IMG_LIST)
+    rendered_img_metadata = os.path.join(rendering_dir,
+                                         cfg.RENDERING.RENDERED_IMG_METADATA)
+    if os.path.isfile(rendered_img_list) and not overwrite:
+        return
+
+    # Load renderer.
+    if cfg.RENDERING.RENDER_ENGINE == 'blender':
+        renderer = ShapeNetRenderer()
+    else:
+        raise NotImplementedError('Unsupported rendering engine: ' +
+                                  cfg.RENDERING.RENDER_ENGINE)
+
+    # Initialize renderer and load model.
+    viewport_size_x = cfg.CONST.IMG_W + cfg.TRAIN.CROP_X
+    viewport_size_y = cfg.CONST.IMG_H + cfg.TRAIN.CROP_Y
+    renderer.initialize([model_paths], viewport_size_x, viewport_size_y)
+    renderer.loadModel()
+
+    # Render images from random viewpoints.
+    view_configs = []
+    rendered_filenames = []
+    for i in range(viewpoints_num):
+        # Set random viewpoint.
+        az, el, depth_ratio = list(
+            *([360, 5, 0.3] * np.random.rand(1, 3) + [0, 25, 0.65]))
+        renderer.setViewpoint(az, el, 0, depth_ratio, 25)
+
+        # Render an image of a given viewpoint.
+        rendered_filename = '%02d.png' % i
+        renderer.result_fn = os.path.join(rendering_dir, rendered_filename)
+
+        rendering, depth = renderer.render(load_model=False, clear_model=False)
+
+        if rendering is None:
+            raise RuntimeError("Rendering failed for unknown reason.")
+
+        # Save the viewpoint.
+        rendered_filenames.append(rendered_filename)
+        view_configs.append([str(az), str(el), '0', str(depth_ratio), '25'])
+
+    renderer.clearModel()
+
+    # Write rendered image list with its metadata.
+    with open(rendered_img_list, 'w') as f:
+        for rendered_filename in rendered_filenames:
+            f.write(rendered_filename + '\n')
+
+    with open(rendered_img_metadata, 'w') as f:
+        for view_config in view_configs:
+            f.write(' '.join(view_config) + '\n')
+
+
+def main():
+    cfg.TRAIN.CROP_X = 10
+    cfg.TRAIN.CROP_Y = 10
+
+    NUM_IMG = cfg.TRAIN.NUM_RENDERING
+    OUTPUT_DIR = 'rendering'  # Subfolder per model to save prerendered images.
+
+    # Multi-process pre-rendering
+    # Blender tends to get slower after it renders few hundred models. Start
+    # over the whole pool every BATCH_SIZE models to boost the speed.
+    NUM_PROCESS = 6
+    BATCH_SIZE = 200
+    args = [(category, model_id, NUM_IMG) for category, model_id in
+            category_model_id_pair(dataset_portion=[0, 1])]
+
+    args_batches = [args[i * BATCH_SIZE:min((i + 1) * BATCH_SIZE, len(args))]
+                    for i in range(len(args) // BATCH_SIZE + 1)]
+
+    for args_batch in args_batches:
+        with Pool(processes=NUM_PROCESS) as pool:
+            pool.starmap(render_model, args_batch)
+
+if __name__ == '__main__':
+    main()