1 /* 2 * Copyright (c) 2010 The WebM project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 12 #include "vpx_scale/yv12config.h" 13 #include "vpx_mem/vpx_mem.h" 14 15 /**************************************************************************** 16 * Exports 17 ****************************************************************************/ 18 19 /**************************************************************************** 20 * 21 ****************************************************************************/ 22 int 23 vp8_yv12_de_alloc_frame_buffer(YV12_BUFFER_CONFIG *ybf) { 24 if (ybf) { 25 vpx_free(ybf->buffer_alloc); 26 27 /* buffer_alloc isn't accessed by most functions. Rather y_buffer, 28 u_buffer and v_buffer point to buffer_alloc and are used. Clear out 29 all of this so that a freed pointer isn't inadvertently used */ 30 vpx_memset(ybf, 0, sizeof(YV12_BUFFER_CONFIG)); 31 } else { 32 return -1; 33 } 34 35 return 0; 36 } 37 38 /**************************************************************************** 39 * 40 ****************************************************************************/ 41 int 42 vp8_yv12_alloc_frame_buffer(YV12_BUFFER_CONFIG *ybf, int width, int height, int border) { 43 /*NOTE:*/ 44 45 if (ybf) { 46 int y_stride = ((width + 2 * border) + 31) & ~31; 47 int yplane_size = (height + 2 * border) * y_stride; 48 int uv_width = width >> 1; 49 int uv_height = height >> 1; 50 /** There is currently a bunch of code which assumes 51 * uv_stride == y_stride/2, so enforce this here. */ 52 int uv_stride = y_stride >> 1; 53 int uvplane_size = (uv_height + border) * uv_stride; 54 55 vp8_yv12_de_alloc_frame_buffer(ybf); 56 57 /** Only support allocating buffers that have a height and width that 58 * are multiples of 16, and a border that's a multiple of 32. 59 * The border restriction is required to get 16-byte alignment of the 60 * start of the chroma rows without intoducing an arbitrary gap 61 * between planes, which would break the semantics of things like 62 * vpx_img_set_rect(). */ 63 if ((width & 0xf) | (height & 0xf) | (border & 0x1f)) 64 return -3; 65 66 ybf->y_width = width; 67 ybf->y_height = height; 68 ybf->y_stride = y_stride; 69 70 ybf->uv_width = uv_width; 71 ybf->uv_height = uv_height; 72 ybf->uv_stride = uv_stride; 73 74 ybf->border = border; 75 ybf->frame_size = yplane_size + 2 * uvplane_size; 76 77 ybf->buffer_alloc = (unsigned char *) vpx_memalign(32, ybf->frame_size); 78 79 if (ybf->buffer_alloc == NULL) 80 return -1; 81 82 ybf->y_buffer = ybf->buffer_alloc + (border * y_stride) + border; 83 ybf->u_buffer = ybf->buffer_alloc + yplane_size + (border / 2 * uv_stride) + border / 2; 84 ybf->v_buffer = ybf->buffer_alloc + yplane_size + uvplane_size + (border / 2 * uv_stride) + border / 2; 85 86 ybf->corrupted = 0; /* assume not currupted by errors */ 87 } else { 88 return -2; 89 } 90 91 return 0; 92 } 93
