Vikas Arora | a241572 | 2012-08-09 16:18:58 -0700 | [diff] [blame] | 1 | // Copyright 2010 Google Inc. All Rights Reserved. |
Eric Hassold | 9aea642 | 2011-01-04 17:22:46 -0800 | [diff] [blame] | 2 | // |
| 3 | // This code is licensed under the same terms as WebM: |
| 4 | // Software License Agreement: http://www.webmproject.org/license/software/ |
| 5 | // Additional IP Rights Grant: http://www.webmproject.org/license/additional/ |
| 6 | // ----------------------------------------------------------------------------- |
| 7 | // |
| 8 | // YUV->RGB conversion function |
| 9 | // |
| 10 | // Author: Skal (pascal.massimino@gmail.com) |
| 11 | |
Vikas Arora | a241572 | 2012-08-09 16:18:58 -0700 | [diff] [blame] | 12 | #include "./yuv.h" |
Eric Hassold | 9aea642 | 2011-01-04 17:22:46 -0800 | [diff] [blame] | 13 | |
| 14 | #if defined(__cplusplus) || defined(c_plusplus) |
| 15 | extern "C" { |
| 16 | #endif |
| 17 | |
| 18 | enum { YUV_HALF = 1 << (YUV_FIX - 1) }; |
| 19 | |
| 20 | int16_t VP8kVToR[256], VP8kUToB[256]; |
| 21 | int32_t VP8kVToG[256], VP8kUToG[256]; |
| 22 | uint8_t VP8kClip[YUV_RANGE_MAX - YUV_RANGE_MIN]; |
Vikas Arora | 4667279 | 2011-07-13 16:37:55 +0530 | [diff] [blame] | 23 | uint8_t VP8kClip4Bits[YUV_RANGE_MAX - YUV_RANGE_MIN]; |
Eric Hassold | 9aea642 | 2011-01-04 17:22:46 -0800 | [diff] [blame] | 24 | |
| 25 | static int done = 0; |
| 26 | |
Vikas Arora | a241572 | 2012-08-09 16:18:58 -0700 | [diff] [blame] | 27 | static WEBP_INLINE uint8_t clip(int v, int max_value) { |
Vikas Arora | 4667279 | 2011-07-13 16:37:55 +0530 | [diff] [blame] | 28 | return v < 0 ? 0 : v > max_value ? max_value : v; |
| 29 | } |
| 30 | |
Vikas Arora | 03d5e34 | 2011-06-02 23:59:44 +0530 | [diff] [blame] | 31 | void VP8YUVInit(void) { |
Eric Hassold | 9aea642 | 2011-01-04 17:22:46 -0800 | [diff] [blame] | 32 | int i; |
| 33 | if (done) { |
| 34 | return; |
| 35 | } |
Vikas Arora | 1e7bf88 | 2013-03-13 16:43:18 -0700 | [diff] [blame^] | 36 | #ifndef USE_YUVj |
Eric Hassold | 9aea642 | 2011-01-04 17:22:46 -0800 | [diff] [blame] | 37 | for (i = 0; i < 256; ++i) { |
| 38 | VP8kVToR[i] = (89858 * (i - 128) + YUV_HALF) >> YUV_FIX; |
| 39 | VP8kUToG[i] = -22014 * (i - 128) + YUV_HALF; |
| 40 | VP8kVToG[i] = -45773 * (i - 128); |
| 41 | VP8kUToB[i] = (113618 * (i - 128) + YUV_HALF) >> YUV_FIX; |
| 42 | } |
| 43 | for (i = YUV_RANGE_MIN; i < YUV_RANGE_MAX; ++i) { |
| 44 | const int k = ((i - 16) * 76283 + YUV_HALF) >> YUV_FIX; |
Vikas Arora | 4667279 | 2011-07-13 16:37:55 +0530 | [diff] [blame] | 45 | VP8kClip[i - YUV_RANGE_MIN] = clip(k, 255); |
| 46 | VP8kClip4Bits[i - YUV_RANGE_MIN] = clip((k + 8) >> 4, 15); |
Eric Hassold | 9aea642 | 2011-01-04 17:22:46 -0800 | [diff] [blame] | 47 | } |
Vikas Arora | 1e7bf88 | 2013-03-13 16:43:18 -0700 | [diff] [blame^] | 48 | #else |
| 49 | for (i = 0; i < 256; ++i) { |
| 50 | VP8kVToR[i] = (91881 * (i - 128) + YUV_HALF) >> YUV_FIX; |
| 51 | VP8kUToG[i] = -22554 * (i - 128) + YUV_HALF; |
| 52 | VP8kVToG[i] = -46802 * (i - 128); |
| 53 | VP8kUToB[i] = (116130 * (i - 128) + YUV_HALF) >> YUV_FIX; |
| 54 | } |
| 55 | for (i = YUV_RANGE_MIN; i < YUV_RANGE_MAX; ++i) { |
| 56 | const int k = i; |
| 57 | VP8kClip[i - YUV_RANGE_MIN] = clip(k, 255); |
| 58 | VP8kClip4Bits[i - YUV_RANGE_MIN] = clip((k + 8) >> 4, 15); |
| 59 | } |
| 60 | #endif |
| 61 | |
Eric Hassold | 9aea642 | 2011-01-04 17:22:46 -0800 | [diff] [blame] | 62 | done = 1; |
| 63 | } |
| 64 | |
| 65 | #if defined(__cplusplus) || defined(c_plusplus) |
| 66 | } // extern "C" |
| 67 | #endif |