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swscale_internal.h
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1 /*
2  * Copyright (C) 2001-2011 Michael Niedermayer <michaelni@gmx.at>
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #ifndef SWSCALE_SWSCALE_INTERNAL_H
22 #define SWSCALE_SWSCALE_INTERNAL_H
23 
24 #include "config.h"
25 
26 #if HAVE_ALTIVEC_H
27 #include <altivec.h>
28 #endif
29 
30 #include "libavutil/avassert.h"
31 #include "libavutil/avutil.h"
32 #include "libavutil/common.h"
33 #include "libavutil/intreadwrite.h"
34 #include "libavutil/log.h"
35 #include "libavutil/pixfmt.h"
36 #include "libavutil/pixdesc.h"
37 
38 #define STR(s) AV_TOSTRING(s) // AV_STRINGIFY is too long
39 
40 #define YUVRGB_TABLE_HEADROOM 128
41 
42 #define FAST_BGR2YV12 // use 7-bit instead of 15-bit coefficients
43 
44 #define MAX_FILTER_SIZE 256
45 
46 #define DITHER1XBPP
47 
48 #if HAVE_BIGENDIAN
49 #define ALT32_CORR (-1)
50 #else
51 #define ALT32_CORR 1
52 #endif
53 
54 #if ARCH_X86_64
55 # define APCK_PTR2 8
56 # define APCK_COEF 16
57 # define APCK_SIZE 24
58 #else
59 # define APCK_PTR2 4
60 # define APCK_COEF 8
61 # define APCK_SIZE 16
62 #endif
63 
64 struct SwsContext;
65 
66 typedef int (*SwsFunc)(struct SwsContext *context, const uint8_t *src[],
67  int srcStride[], int srcSliceY, int srcSliceH,
68  uint8_t *dst[], int dstStride[]);
69 
70 /**
71  * Write one line of horizontally scaled data to planar output
72  * without any additional vertical scaling (or point-scaling).
73  *
74  * @param src scaled source data, 15bit for 8-10bit output,
75  * 19-bit for 16bit output (in int32_t)
76  * @param dest pointer to the output plane. For >8bit
77  * output, this is in uint16_t
78  * @param dstW width of destination in pixels
79  * @param dither ordered dither array of type int16_t and size 8
80  * @param offset Dither offset
81  */
82 typedef void (*yuv2planar1_fn)(const int16_t *src, uint8_t *dest, int dstW,
83  const uint8_t *dither, int offset);
84 
85 /**
86  * Write one line of horizontally scaled data to planar output
87  * with multi-point vertical scaling between input pixels.
88  *
89  * @param filter vertical luma/alpha scaling coefficients, 12bit [0,4096]
90  * @param src scaled luma (Y) or alpha (A) source data, 15bit for 8-10bit output,
91  * 19-bit for 16bit output (in int32_t)
92  * @param filterSize number of vertical input lines to scale
93  * @param dest pointer to output plane. For >8bit
94  * output, this is in uint16_t
95  * @param dstW width of destination pixels
96  * @param offset Dither offset
97  */
98 typedef void (*yuv2planarX_fn)(const int16_t *filter, int filterSize,
99  const int16_t **src, uint8_t *dest, int dstW,
100  const uint8_t *dither, int offset);
101 
102 /**
103  * Write one line of horizontally scaled chroma to interleaved output
104  * with multi-point vertical scaling between input pixels.
105  *
106  * @param c SWS scaling context
107  * @param chrFilter vertical chroma scaling coefficients, 12bit [0,4096]
108  * @param chrUSrc scaled chroma (U) source data, 15bit for 8-10bit output,
109  * 19-bit for 16bit output (in int32_t)
110  * @param chrVSrc scaled chroma (V) source data, 15bit for 8-10bit output,
111  * 19-bit for 16bit output (in int32_t)
112  * @param chrFilterSize number of vertical chroma input lines to scale
113  * @param dest pointer to the output plane. For >8bit
114  * output, this is in uint16_t
115  * @param dstW width of chroma planes
116  */
118  const int16_t *chrFilter,
119  int chrFilterSize,
120  const int16_t **chrUSrc,
121  const int16_t **chrVSrc,
122  uint8_t *dest, int dstW);
123 
124 /**
125  * Write one line of horizontally scaled Y/U/V/A to packed-pixel YUV/RGB
126  * output without any additional vertical scaling (or point-scaling). Note
127  * that this function may do chroma scaling, see the "uvalpha" argument.
128  *
129  * @param c SWS scaling context
130  * @param lumSrc scaled luma (Y) source data, 15bit for 8-10bit output,
131  * 19-bit for 16bit output (in int32_t)
132  * @param chrUSrc scaled chroma (U) source data, 15bit for 8-10bit output,
133  * 19-bit for 16bit output (in int32_t)
134  * @param chrVSrc scaled chroma (V) source data, 15bit for 8-10bit output,
135  * 19-bit for 16bit output (in int32_t)
136  * @param alpSrc scaled alpha (A) source data, 15bit for 8-10bit output,
137  * 19-bit for 16bit output (in int32_t)
138  * @param dest pointer to the output plane. For 16bit output, this is
139  * uint16_t
140  * @param dstW width of lumSrc and alpSrc in pixels, number of pixels
141  * to write into dest[]
142  * @param uvalpha chroma scaling coefficient for the second line of chroma
143  * pixels, either 2048 or 0. If 0, one chroma input is used
144  * for 2 output pixels (or if the SWS_FLAG_FULL_CHR_INT flag
145  * is set, it generates 1 output pixel). If 2048, two chroma
146  * input pixels should be averaged for 2 output pixels (this
147  * only happens if SWS_FLAG_FULL_CHR_INT is not set)
148  * @param y vertical line number for this output. This does not need
149  * to be used to calculate the offset in the destination,
150  * but can be used to generate comfort noise using dithering
151  * for some output formats.
152  */
153 typedef void (*yuv2packed1_fn)(struct SwsContext *c, const int16_t *lumSrc,
154  const int16_t *chrUSrc[2],
155  const int16_t *chrVSrc[2],
156  const int16_t *alpSrc, uint8_t *dest,
157  int dstW, int uvalpha, int y);
158 /**
159  * Write one line of horizontally scaled Y/U/V/A to packed-pixel YUV/RGB
160  * output by doing bilinear scaling between two input lines.
161  *
162  * @param c SWS scaling context
163  * @param lumSrc scaled luma (Y) source data, 15bit for 8-10bit output,
164  * 19-bit for 16bit output (in int32_t)
165  * @param chrUSrc scaled chroma (U) source data, 15bit for 8-10bit output,
166  * 19-bit for 16bit output (in int32_t)
167  * @param chrVSrc scaled chroma (V) source data, 15bit for 8-10bit output,
168  * 19-bit for 16bit output (in int32_t)
169  * @param alpSrc scaled alpha (A) source data, 15bit for 8-10bit output,
170  * 19-bit for 16bit output (in int32_t)
171  * @param dest pointer to the output plane. For 16bit output, this is
172  * uint16_t
173  * @param dstW width of lumSrc and alpSrc in pixels, number of pixels
174  * to write into dest[]
175  * @param yalpha luma/alpha scaling coefficients for the second input line.
176  * The first line's coefficients can be calculated by using
177  * 4096 - yalpha
178  * @param uvalpha chroma scaling coefficient for the second input line. The
179  * first line's coefficients can be calculated by using
180  * 4096 - uvalpha
181  * @param y vertical line number for this output. This does not need
182  * to be used to calculate the offset in the destination,
183  * but can be used to generate comfort noise using dithering
184  * for some output formats.
185  */
186 typedef void (*yuv2packed2_fn)(struct SwsContext *c, const int16_t *lumSrc[2],
187  const int16_t *chrUSrc[2],
188  const int16_t *chrVSrc[2],
189  const int16_t *alpSrc[2],
190  uint8_t *dest,
191  int dstW, int yalpha, int uvalpha, int y);
192 /**
193  * Write one line of horizontally scaled Y/U/V/A to packed-pixel YUV/RGB
194  * output by doing multi-point vertical scaling between input pixels.
195  *
196  * @param c SWS scaling context
197  * @param lumFilter vertical luma/alpha scaling coefficients, 12bit [0,4096]
198  * @param lumSrc scaled luma (Y) source data, 15bit for 8-10bit output,
199  * 19-bit for 16bit output (in int32_t)
200  * @param lumFilterSize number of vertical luma/alpha input lines to scale
201  * @param chrFilter vertical chroma scaling coefficients, 12bit [0,4096]
202  * @param chrUSrc scaled chroma (U) source data, 15bit for 8-10bit output,
203  * 19-bit for 16bit output (in int32_t)
204  * @param chrVSrc scaled chroma (V) source data, 15bit for 8-10bit output,
205  * 19-bit for 16bit output (in int32_t)
206  * @param chrFilterSize number of vertical chroma input lines to scale
207  * @param alpSrc scaled alpha (A) source data, 15bit for 8-10bit output,
208  * 19-bit for 16bit output (in int32_t)
209  * @param dest pointer to the output plane. For 16bit output, this is
210  * uint16_t
211  * @param dstW width of lumSrc and alpSrc in pixels, number of pixels
212  * to write into dest[]
213  * @param y vertical line number for this output. This does not need
214  * to be used to calculate the offset in the destination,
215  * but can be used to generate comfort noise using dithering
216  * or some output formats.
217  */
218 typedef void (*yuv2packedX_fn)(struct SwsContext *c, const int16_t *lumFilter,
219  const int16_t **lumSrc, int lumFilterSize,
220  const int16_t *chrFilter,
221  const int16_t **chrUSrc,
222  const int16_t **chrVSrc, int chrFilterSize,
223  const int16_t **alpSrc, uint8_t *dest,
224  int dstW, int y);
225 
226 /**
227  * Write one line of horizontally scaled Y/U/V/A to YUV/RGB
228  * output by doing multi-point vertical scaling between input pixels.
229  *
230  * @param c SWS scaling context
231  * @param lumFilter vertical luma/alpha scaling coefficients, 12bit [0,4096]
232  * @param lumSrc scaled luma (Y) source data, 15bit for 8-10bit output,
233  * 19-bit for 16bit output (in int32_t)
234  * @param lumFilterSize number of vertical luma/alpha input lines to scale
235  * @param chrFilter vertical chroma scaling coefficients, 12bit [0,4096]
236  * @param chrUSrc scaled chroma (U) source data, 15bit for 8-10bit output,
237  * 19-bit for 16bit output (in int32_t)
238  * @param chrVSrc scaled chroma (V) source data, 15bit for 8-10bit output,
239  * 19-bit for 16bit output (in int32_t)
240  * @param chrFilterSize number of vertical chroma input lines to scale
241  * @param alpSrc scaled alpha (A) source data, 15bit for 8-10bit output,
242  * 19-bit for 16bit output (in int32_t)
243  * @param dest pointer to the output planes. For 16bit output, this is
244  * uint16_t
245  * @param dstW width of lumSrc and alpSrc in pixels, number of pixels
246  * to write into dest[]
247  * @param y vertical line number for this output. This does not need
248  * to be used to calculate the offset in the destination,
249  * but can be used to generate comfort noise using dithering
250  * or some output formats.
251  */
252 typedef void (*yuv2anyX_fn)(struct SwsContext *c, const int16_t *lumFilter,
253  const int16_t **lumSrc, int lumFilterSize,
254  const int16_t *chrFilter,
255  const int16_t **chrUSrc,
256  const int16_t **chrVSrc, int chrFilterSize,
257  const int16_t **alpSrc, uint8_t **dest,
258  int dstW, int y);
259 
260 /* This struct should be aligned on at least a 32-byte boundary. */
261 typedef struct SwsContext {
262  /**
263  * info on struct for av_log
264  */
266 
267  /**
268  * Note that src, dst, srcStride, dstStride will be copied in the
269  * sws_scale() wrapper so they can be freely modified here.
270  */
272  int srcW; ///< Width of source luma/alpha planes.
273  int srcH; ///< Height of source luma/alpha planes.
274  int dstH; ///< Height of destination luma/alpha planes.
275  int chrSrcW; ///< Width of source chroma planes.
276  int chrSrcH; ///< Height of source chroma planes.
277  int chrDstW; ///< Width of destination chroma planes.
278  int chrDstH; ///< Height of destination chroma planes.
281  enum AVPixelFormat dstFormat; ///< Destination pixel format.
282  enum AVPixelFormat srcFormat; ///< Source pixel format.
283  int dstFormatBpp; ///< Number of bits per pixel of the destination pixel format.
284  int srcFormatBpp; ///< Number of bits per pixel of the source pixel format.
286  int chrSrcHSubSample; ///< Binary logarithm of horizontal subsampling factor between luma/alpha and chroma planes in source image.
287  int chrSrcVSubSample; ///< Binary logarithm of vertical subsampling factor between luma/alpha and chroma planes in source image.
288  int chrDstHSubSample; ///< Binary logarithm of horizontal subsampling factor between luma/alpha and chroma planes in destination image.
289  int chrDstVSubSample; ///< Binary logarithm of vertical subsampling factor between luma/alpha and chroma planes in destination image.
290  int vChrDrop; ///< Binary logarithm of extra vertical subsampling factor in source image chroma planes specified by user.
291  int sliceDir; ///< Direction that slices are fed to the scaler (1 = top-to-bottom, -1 = bottom-to-top).
292  double param[2]; ///< Input parameters for scaling algorithms that need them.
293 
294  uint32_t pal_yuv[256];
295  uint32_t pal_rgb[256];
296 
297  /**
298  * @name Scaled horizontal lines ring buffer.
299  * The horizontal scaler keeps just enough scaled lines in a ring buffer
300  * so they may be passed to the vertical scaler. The pointers to the
301  * allocated buffers for each line are duplicated in sequence in the ring
302  * buffer to simplify indexing and avoid wrapping around between lines
303  * inside the vertical scaler code. The wrapping is done before the
304  * vertical scaler is called.
305  */
306  //@{
307  int16_t **lumPixBuf; ///< Ring buffer for scaled horizontal luma plane lines to be fed to the vertical scaler.
308  int16_t **chrUPixBuf; ///< Ring buffer for scaled horizontal chroma plane lines to be fed to the vertical scaler.
309  int16_t **chrVPixBuf; ///< Ring buffer for scaled horizontal chroma plane lines to be fed to the vertical scaler.
310  int16_t **alpPixBuf; ///< Ring buffer for scaled horizontal alpha plane lines to be fed to the vertical scaler.
311  int vLumBufSize; ///< Number of vertical luma/alpha lines allocated in the ring buffer.
312  int vChrBufSize; ///< Number of vertical chroma lines allocated in the ring buffer.
313  int lastInLumBuf; ///< Last scaled horizontal luma/alpha line from source in the ring buffer.
314  int lastInChrBuf; ///< Last scaled horizontal chroma line from source in the ring buffer.
315  int lumBufIndex; ///< Index in ring buffer of the last scaled horizontal luma/alpha line from source.
316  int chrBufIndex; ///< Index in ring buffer of the last scaled horizontal chroma line from source.
317  //@}
318 
320 
321  /**
322  * @name Horizontal and vertical filters.
323  * To better understand the following fields, here is a pseudo-code of
324  * their usage in filtering a horizontal line:
325  * @code
326  * for (i = 0; i < width; i++) {
327  * dst[i] = 0;
328  * for (j = 0; j < filterSize; j++)
329  * dst[i] += src[ filterPos[i] + j ] * filter[ filterSize * i + j ];
330  * dst[i] >>= FRAC_BITS; // The actual implementation is fixed-point.
331  * }
332  * @endcode
333  */
334  //@{
335  int16_t *hLumFilter; ///< Array of horizontal filter coefficients for luma/alpha planes.
336  int16_t *hChrFilter; ///< Array of horizontal filter coefficients for chroma planes.
337  int16_t *vLumFilter; ///< Array of vertical filter coefficients for luma/alpha planes.
338  int16_t *vChrFilter; ///< Array of vertical filter coefficients for chroma planes.
339  int32_t *hLumFilterPos; ///< Array of horizontal filter starting positions for each dst[i] for luma/alpha planes.
340  int32_t *hChrFilterPos; ///< Array of horizontal filter starting positions for each dst[i] for chroma planes.
341  int32_t *vLumFilterPos; ///< Array of vertical filter starting positions for each dst[i] for luma/alpha planes.
342  int32_t *vChrFilterPos; ///< Array of vertical filter starting positions for each dst[i] for chroma planes.
343  int hLumFilterSize; ///< Horizontal filter size for luma/alpha pixels.
344  int hChrFilterSize; ///< Horizontal filter size for chroma pixels.
345  int vLumFilterSize; ///< Vertical filter size for luma/alpha pixels.
346  int vChrFilterSize; ///< Vertical filter size for chroma pixels.
347  //@}
348 
349  int lumMmxextFilterCodeSize; ///< Runtime-generated MMXEXT horizontal fast bilinear scaler code size for luma/alpha planes.
350  int chrMmxextFilterCodeSize; ///< Runtime-generated MMXEXT horizontal fast bilinear scaler code size for chroma planes.
351  uint8_t *lumMmxextFilterCode; ///< Runtime-generated MMXEXT horizontal fast bilinear scaler code for luma/alpha planes.
352  uint8_t *chrMmxextFilterCode; ///< Runtime-generated MMXEXT horizontal fast bilinear scaler code for chroma planes.
353 
355 
356  int dstY; ///< Last destination vertical line output from last slice.
357  int flags; ///< Flags passed by the user to select scaler algorithm, optimizations, subsampling, etc...
358  void *yuvTable; // pointer to the yuv->rgb table start so it can be freed()
363 
364  int *dither_error[4];
365 
366  //Colorspace stuff
367  int contrast, brightness, saturation; // for sws_getColorspaceDetails
370  int srcRange; ///< 0 = MPG YUV range, 1 = JPG YUV range (source image).
371  int dstRange; ///< 0 = MPG YUV range, 1 = JPG YUV range (destination image).
380 
381 #define RED_DITHER "0*8"
382 #define GREEN_DITHER "1*8"
383 #define BLUE_DITHER "2*8"
384 #define Y_COEFF "3*8"
385 #define VR_COEFF "4*8"
386 #define UB_COEFF "5*8"
387 #define VG_COEFF "6*8"
388 #define UG_COEFF "7*8"
389 #define Y_OFFSET "8*8"
390 #define U_OFFSET "9*8"
391 #define V_OFFSET "10*8"
392 #define LUM_MMX_FILTER_OFFSET "11*8"
393 #define CHR_MMX_FILTER_OFFSET "11*8+4*4*256"
394 #define DSTW_OFFSET "11*8+4*4*256*2" //do not change, it is hardcoded in the ASM
395 #define ESP_OFFSET "11*8+4*4*256*2+8"
396 #define VROUNDER_OFFSET "11*8+4*4*256*2+16"
397 #define U_TEMP "11*8+4*4*256*2+24"
398 #define V_TEMP "11*8+4*4*256*2+32"
399 #define Y_TEMP "11*8+4*4*256*2+40"
400 #define ALP_MMX_FILTER_OFFSET "11*8+4*4*256*2+48"
401 #define UV_OFF_PX "11*8+4*4*256*3+48"
402 #define UV_OFF_BYTE "11*8+4*4*256*3+56"
403 #define DITHER16 "11*8+4*4*256*3+64"
404 #define DITHER32 "11*8+4*4*256*3+80"
405 
406  DECLARE_ALIGNED(8, uint64_t, redDither);
409 
410  DECLARE_ALIGNED(8, uint64_t, yCoeff);
411  DECLARE_ALIGNED(8, uint64_t, vrCoeff);
412  DECLARE_ALIGNED(8, uint64_t, ubCoeff);
413  DECLARE_ALIGNED(8, uint64_t, vgCoeff);
414  DECLARE_ALIGNED(8, uint64_t, ugCoeff);
415  DECLARE_ALIGNED(8, uint64_t, yOffset);
416  DECLARE_ALIGNED(8, uint64_t, uOffset);
417  DECLARE_ALIGNED(8, uint64_t, vOffset);
420  int dstW; ///< Width of destination luma/alpha planes.
421  DECLARE_ALIGNED(8, uint64_t, esp);
422  DECLARE_ALIGNED(8, uint64_t, vRounder);
423  DECLARE_ALIGNED(8, uint64_t, u_temp);
424  DECLARE_ALIGNED(8, uint64_t, v_temp);
425  DECLARE_ALIGNED(8, uint64_t, y_temp);
427  // alignment of these values is not necessary, but merely here
428  // to maintain the same offset across x8632 and x86-64. Once we
429  // use proper offset macros in the asm, they can be removed.
430  DECLARE_ALIGNED(8, ptrdiff_t, uv_off); ///< offset (in pixels) between u and v planes
431  DECLARE_ALIGNED(8, ptrdiff_t, uv_offx2); ///< offset (in bytes) between u and v planes
432  DECLARE_ALIGNED(8, uint16_t, dither16)[8];
433  DECLARE_ALIGNED(8, uint32_t, dither32)[8];
434 
436 
437 #if HAVE_ALTIVEC
438  vector signed short CY;
439  vector signed short CRV;
440  vector signed short CBU;
441  vector signed short CGU;
442  vector signed short CGV;
443  vector signed short OY;
444  vector unsigned short CSHIFT;
445  vector signed short *vYCoeffsBank, *vCCoeffsBank;
446 #endif
447 
448 #if ARCH_BFIN
449  DECLARE_ALIGNED(4, uint32_t, oy);
450  DECLARE_ALIGNED(4, uint32_t, oc);
451  DECLARE_ALIGNED(4, uint32_t, zero);
452  DECLARE_ALIGNED(4, uint32_t, cy);
453  DECLARE_ALIGNED(4, uint32_t, crv);
454  DECLARE_ALIGNED(4, uint32_t, rmask);
455  DECLARE_ALIGNED(4, uint32_t, cbu);
456  DECLARE_ALIGNED(4, uint32_t, bmask);
457  DECLARE_ALIGNED(4, uint32_t, cgu);
458  DECLARE_ALIGNED(4, uint32_t, cgv);
459  DECLARE_ALIGNED(4, uint32_t, gmask);
460 #endif
461 
462 #if HAVE_VIS
463  DECLARE_ALIGNED(8, uint64_t, sparc_coeffs)[10];
464 #endif
466 
467  /* function pointers for swScale() */
475 
476  /// Unscaled conversion of luma plane to YV12 for horizontal scaler.
477  void (*lumToYV12)(uint8_t *dst, const uint8_t *src, const uint8_t *src2, const uint8_t *src3,
478  int width, uint32_t *pal);
479  /// Unscaled conversion of alpha plane to YV12 for horizontal scaler.
480  void (*alpToYV12)(uint8_t *dst, const uint8_t *src, const uint8_t *src2, const uint8_t *src3,
481  int width, uint32_t *pal);
482  /// Unscaled conversion of chroma planes to YV12 for horizontal scaler.
483  void (*chrToYV12)(uint8_t *dstU, uint8_t *dstV,
484  const uint8_t *src1, const uint8_t *src2, const uint8_t *src3,
485  int width, uint32_t *pal);
486 
487  /**
488  * Functions to read planar input, such as planar RGB, and convert
489  * internally to Y/UV.
490  */
491  /** @{ */
492  void (*readLumPlanar)(uint8_t *dst, const uint8_t *src[4], int width);
493  void (*readChrPlanar)(uint8_t *dstU, uint8_t *dstV, const uint8_t *src[4],
494  int width);
495  /** @} */
496 
497  /**
498  * Scale one horizontal line of input data using a bilinear filter
499  * to produce one line of output data. Compared to SwsContext->hScale(),
500  * please take note of the following caveats when using these:
501  * - Scaling is done using only 7bit instead of 14bit coefficients.
502  * - You can use no more than 5 input pixels to produce 4 output
503  * pixels. Therefore, this filter should not be used for downscaling
504  * by more than ~20% in width (because that equals more than 5/4th
505  * downscaling and thus more than 5 pixels input per 4 pixels output).
506  * - In general, bilinear filters create artifacts during downscaling
507  * (even when <20%), because one output pixel will span more than one
508  * input pixel, and thus some pixels will need edges of both neighbor
509  * pixels to interpolate the output pixel. Since you can use at most
510  * two input pixels per output pixel in bilinear scaling, this is
511  * impossible and thus downscaling by any size will create artifacts.
512  * To enable this type of scaling, set SWS_FLAG_FAST_BILINEAR
513  * in SwsContext->flags.
514  */
515  /** @{ */
517  int16_t *dst, int dstWidth,
518  const uint8_t *src, int srcW, int xInc);
520  int16_t *dst1, int16_t *dst2, int dstWidth,
521  const uint8_t *src1, const uint8_t *src2,
522  int srcW, int xInc);
523  /** @} */
524 
525  /**
526  * Scale one horizontal line of input data using a filter over the input
527  * lines, to produce one (differently sized) line of output data.
528  *
529  * @param dst pointer to destination buffer for horizontally scaled
530  * data. If the number of bits per component of one
531  * destination pixel (SwsContext->dstBpc) is <= 10, data
532  * will be 15bpc in 16bits (int16_t) width. Else (i.e.
533  * SwsContext->dstBpc == 16), data will be 19bpc in
534  * 32bits (int32_t) width.
535  * @param dstW width of destination image
536  * @param src pointer to source data to be scaled. If the number of
537  * bits per component of a source pixel (SwsContext->srcBpc)
538  * is 8, this is 8bpc in 8bits (uint8_t) width. Else
539  * (i.e. SwsContext->dstBpc > 8), this is native depth
540  * in 16bits (uint16_t) width. In other words, for 9-bit
541  * YUV input, this is 9bpc, for 10-bit YUV input, this is
542  * 10bpc, and for 16-bit RGB or YUV, this is 16bpc.
543  * @param filter filter coefficients to be used per output pixel for
544  * scaling. This contains 14bpp filtering coefficients.
545  * Guaranteed to contain dstW * filterSize entries.
546  * @param filterPos position of the first input pixel to be used for
547  * each output pixel during scaling. Guaranteed to
548  * contain dstW entries.
549  * @param filterSize the number of input coefficients to be used (and
550  * thus the number of input pixels to be used) for
551  * creating a single output pixel. Is aligned to 4
552  * (and input coefficients thus padded with zeroes)
553  * to simplify creating SIMD code.
554  */
555  /** @{ */
556  void (*hyScale)(struct SwsContext *c, int16_t *dst, int dstW,
557  const uint8_t *src, const int16_t *filter,
558  const int32_t *filterPos, int filterSize);
559  void (*hcScale)(struct SwsContext *c, int16_t *dst, int dstW,
560  const uint8_t *src, const int16_t *filter,
561  const int32_t *filterPos, int filterSize);
562  /** @} */
563 
564  /// Color range conversion function for luma plane if needed.
565  void (*lumConvertRange)(int16_t *dst, int width);
566  /// Color range conversion function for chroma planes if needed.
567  void (*chrConvertRange)(int16_t *dst1, int16_t *dst2, int width);
568 
569  int needs_hcscale; ///< Set if there are chroma planes to be converted.
570 } SwsContext;
571 //FIXME check init (where 0)
572 
574 int ff_yuv2rgb_c_init_tables(SwsContext *c, const int inv_table[4],
575  int fullRange, int brightness,
576  int contrast, int saturation);
577 
578 void ff_yuv2rgb_init_tables_altivec(SwsContext *c, const int inv_table[4],
579  int brightness, int contrast, int saturation);
581  int lastInLumBuf, int lastInChrBuf);
582 
588 
589 #if FF_API_SWS_FORMAT_NAME
590 /**
591  * @deprecated Use av_get_pix_fmt_name() instead.
592  */
594 const char *sws_format_name(enum AVPixelFormat format);
595 #endif
596 
598 {
599  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
600  av_assert0(desc);
601  return desc->comp[0].depth_minus1 == 15;
602 }
603 
605 {
606  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
607  av_assert0(desc);
608  return desc->comp[0].depth_minus1 >= 8 && desc->comp[0].depth_minus1 <= 13;
609 }
610 
611 #define isNBPS(x) is9_OR_10BPS(x)
612 
614 {
615  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
616  av_assert0(desc);
617  return desc->flags & PIX_FMT_BE;
618 }
619 
621 {
622  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
623  av_assert0(desc);
624  return !(desc->flags & PIX_FMT_RGB) && desc->nb_components >= 2;
625 }
626 
628 {
629  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
630  av_assert0(desc);
631  return ((desc->flags & PIX_FMT_PLANAR) && isYUV(pix_fmt));
632 }
633 
635 {
636  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
637  av_assert0(desc);
638  return (desc->flags & PIX_FMT_RGB);
639 }
640 
641 #if 0 // FIXME
642 #define isGray(x) \
643  (!(av_pix_fmt_desc_get(x)->flags & PIX_FMT_PAL) && \
644  av_pix_fmt_desc_get(x)->nb_components <= 2)
645 #else
646 #define isGray(x) \
647  ((x) == AV_PIX_FMT_GRAY8 || \
648  (x) == AV_PIX_FMT_Y400A || \
649  (x) == AV_PIX_FMT_GRAY16BE || \
650  (x) == AV_PIX_FMT_GRAY16LE)
651 #endif
652 
653 #define isRGBinInt(x) \
654  ( \
655  (x) == AV_PIX_FMT_RGB48BE || \
656  (x) == AV_PIX_FMT_RGB48LE || \
657  (x) == AV_PIX_FMT_RGBA64BE || \
658  (x) == AV_PIX_FMT_RGBA64LE || \
659  (x) == AV_PIX_FMT_RGB32 || \
660  (x) == AV_PIX_FMT_RGB32_1 || \
661  (x) == AV_PIX_FMT_RGB24 || \
662  (x) == AV_PIX_FMT_RGB565BE || \
663  (x) == AV_PIX_FMT_RGB565LE || \
664  (x) == AV_PIX_FMT_RGB555BE || \
665  (x) == AV_PIX_FMT_RGB555LE || \
666  (x) == AV_PIX_FMT_RGB444BE || \
667  (x) == AV_PIX_FMT_RGB444LE || \
668  (x) == AV_PIX_FMT_RGB8 || \
669  (x) == AV_PIX_FMT_RGB4 || \
670  (x) == AV_PIX_FMT_RGB4_BYTE || \
671  (x) == AV_PIX_FMT_MONOBLACK || \
672  (x) == AV_PIX_FMT_MONOWHITE \
673  )
674 #define isBGRinInt(x) \
675  ( \
676  (x) == AV_PIX_FMT_BGR48BE || \
677  (x) == AV_PIX_FMT_BGR48LE || \
678  (x) == AV_PIX_FMT_BGRA64BE || \
679  (x) == AV_PIX_FMT_BGRA64LE || \
680  (x) == AV_PIX_FMT_BGR32 || \
681  (x) == AV_PIX_FMT_BGR32_1 || \
682  (x) == AV_PIX_FMT_BGR24 || \
683  (x) == AV_PIX_FMT_BGR565BE || \
684  (x) == AV_PIX_FMT_BGR565LE || \
685  (x) == AV_PIX_FMT_BGR555BE || \
686  (x) == AV_PIX_FMT_BGR555LE || \
687  (x) == AV_PIX_FMT_BGR444BE || \
688  (x) == AV_PIX_FMT_BGR444LE || \
689  (x) == AV_PIX_FMT_BGR8 || \
690  (x) == AV_PIX_FMT_BGR4 || \
691  (x) == AV_PIX_FMT_BGR4_BYTE || \
692  (x) == AV_PIX_FMT_MONOBLACK || \
693  (x) == AV_PIX_FMT_MONOWHITE \
694  )
695 
696 #define isRGBinBytes(x) ( \
697  (x) == AV_PIX_FMT_RGB48BE \
698  || (x) == AV_PIX_FMT_RGB48LE \
699  || (x) == AV_PIX_FMT_RGBA64BE \
700  || (x) == AV_PIX_FMT_RGBA64LE \
701  || (x) == AV_PIX_FMT_RGBA \
702  || (x) == AV_PIX_FMT_ARGB \
703  || (x) == AV_PIX_FMT_RGB24 \
704  )
705 #define isBGRinBytes(x) ( \
706  (x) == AV_PIX_FMT_BGR48BE \
707  || (x) == AV_PIX_FMT_BGR48LE \
708  || (x) == AV_PIX_FMT_BGRA64BE \
709  || (x) == AV_PIX_FMT_BGRA64LE \
710  || (x) == AV_PIX_FMT_BGRA \
711  || (x) == AV_PIX_FMT_ABGR \
712  || (x) == AV_PIX_FMT_BGR24 \
713  )
714 
715 #define isAnyRGB(x) \
716  ( \
717  isRGBinInt(x) || \
718  isBGRinInt(x) || \
719  isRGB(x) || \
720  (x)==AV_PIX_FMT_GBRP9LE || \
721  (x)==AV_PIX_FMT_GBRP9BE || \
722  (x)==AV_PIX_FMT_GBRP10LE || \
723  (x)==AV_PIX_FMT_GBRP10BE || \
724  (x)==AV_PIX_FMT_GBRP12LE || \
725  (x)==AV_PIX_FMT_GBRP12BE || \
726  (x)==AV_PIX_FMT_GBRP14LE || \
727  (x)==AV_PIX_FMT_GBRP14BE || \
728  (x)==AV_PIX_FMT_GBR24P \
729  )
730 
732 {
733  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
734  av_assert0(desc);
735  return desc->flags & PIX_FMT_ALPHA;
736 }
737 
738 #if 1
739 #define isPacked(x) ( \
740  (x)==AV_PIX_FMT_PAL8 \
741  || (x)==AV_PIX_FMT_YUYV422 \
742  || (x)==AV_PIX_FMT_UYVY422 \
743  || (x)==AV_PIX_FMT_Y400A \
744  || isRGBinInt(x) \
745  || isBGRinInt(x) \
746  )
747 #else
749 {
750  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
751  av_assert0(desc);
752  return ((desc->nb_components >= 2 && !(desc->flags & PIX_FMT_PLANAR)) ||
753  pix_fmt == AV_PIX_FMT_PAL8);
754 }
755 
756 #endif
758 {
759  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
760  av_assert0(desc);
761  return (desc->nb_components >= 2 && (desc->flags & PIX_FMT_PLANAR));
762 }
763 
765 {
766  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
767  av_assert0(desc);
768  return ((desc->flags & (PIX_FMT_PLANAR | PIX_FMT_RGB)) == PIX_FMT_RGB);
769 }
770 
772 {
773  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
774  av_assert0(desc);
775  return ((desc->flags & (PIX_FMT_PLANAR | PIX_FMT_RGB)) ==
777 }
778 
780 {
781  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
782  av_assert0(desc);
783  return (desc->flags & PIX_FMT_PAL) || (desc->flags & PIX_FMT_PSEUDOPAL);
784 }
785 
786 extern const uint64_t ff_dither4[2];
787 extern const uint64_t ff_dither8[2];
788 extern const uint8_t dithers[8][8][8];
789 extern const uint16_t dither_scale[15][16];
790 
791 
792 extern const AVClass sws_context_class;
793 
794 /**
795  * Set c->swScale to an unscaled converter if one exists for the specific
796  * source and destination formats, bit depths, flags, etc.
797  */
799 
801 
802 /**
803  * Return function pointer to fastest main scaler path function depending
804  * on architecture and available optimizations.
805  */
807 
819 
820 static inline void fillPlane16(uint8_t *plane, int stride, int width, int height, int y,
821  int alpha, int bits, const int big_endian)
822 {
823  int i, j;
824  uint8_t *ptr = plane + stride * y;
825  int v = alpha ? 0xFFFF>>(15-bits) : (1<<bits);
826  for (i = 0; i < height; i++) {
827 #define FILL(wfunc) \
828  for (j = 0; j < width; j++) {\
829  wfunc(ptr+2*j, v);\
830  }
831  if (big_endian) {
832  FILL(AV_WB16);
833  } else {
834  FILL(AV_WL16);
835  }
836  ptr += stride;
837  }
838 }
839 
840 #endif /* SWSCALE_SWSCALE_INTERNAL_H */