2 * Copyright (c) 2010 The WebM project authors. All Rights Reserved.
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.
10 * Based on code from the OggTheora software codec source code,
11 * Copyright (C) 2002-2010 The Xiph.Org Foundation and contributors.
17 static int y4m_parse_tags(y4m_input
*_y4m
,char *_tags
){
26 got_w
=got_h
=got_fps
=got_interlace
=got_par
=got_chroma
=0;
28 /*Skip any leading spaces.*/
30 /*If that's all we have, stop.*/
32 /*Find the end of this tag.*/
33 for(q
=p
+1;*q
!='\0'&&*q
!=' ';q
++);
37 if(sscanf(p
+1,"%d",&_y4m
->pic_w
)!=1)return -1;
41 if(sscanf(p
+1,"%d",&_y4m
->pic_h
)!=1)return -1;
45 if(sscanf(p
+1,"%d:%d",&_y4m
->fps_n
,&_y4m
->fps_d
)!=2){
55 if(sscanf(p
+1,"%d:%d",&_y4m
->par_n
,&_y4m
->par_d
)!=2){
62 memcpy(_y4m
->chroma_type
,p
+1,q
-p
-1);
63 _y4m
->chroma_type
[q
-p
-1]='\0';
66 /*Ignore unknown tags.*/
69 if(!got_w
||!got_h
||!got_fps
)return -1;
70 if(!got_interlace
)_y4m
->interlace
='?';
71 if(!got_par
)_y4m
->par_n
=_y4m
->par_d
=0;
72 /*Chroma-type is not specified in older files, e.g., those generated by
74 if(!got_chroma
)strcpy(_y4m
->chroma_type
,"420");
80 /*All anti-aliasing filters in the following conversion functions are based on
81 one of two window functions:
82 The 6-tap Lanczos window (for down-sampling and shifts):
83 sinc(\pi*t)*sinc(\pi*t/3), |t|<3 (sinc(t)==sin(t)/t)
85 The 4-tap Mitchell window (for up-sampling):
86 7|t|^3-12|t|^2+16/3, |t|<1
87 -(7/3)|x|^3+12|x|^2-20|x|+32/3, |t|<2
89 The number of taps is intentionally kept small to reduce computational
90 overhead and limit ringing.
92 The taps from these filters are scaled so that their sum is 1, and the result
93 is scaled by 128 and rounded to integers to create a filter whose
94 intermediate values fit inside 16 bits.
95 Coefficients are rounded in such a way as to ensure their sum is still 128,
96 which is usually equivalent to normal rounding.
98 Conversions which require both horizontal and vertical filtering could
99 have these steps pipelined, for less memory consumption and better cache
100 performance, but we do them separately for simplicity.*/
102 #define OC_MINI(_a,_b) ((_a)>(_b)?(_b):(_a))
103 #define OC_MAXI(_a,_b) ((_a)<(_b)?(_b):(_a))
104 #define OC_CLAMPI(_a,_b,_c) (OC_MAXI(_a,OC_MINI(_b,_c)))
106 /*420jpeg chroma samples are sited like:
107 Y-------Y-------Y-------Y-------
111 Y-------Y-------Y-------Y-------
115 Y-------Y-------Y-------Y-------
119 Y-------Y-------Y-------Y-------
124 420mpeg2 chroma samples are sited like:
125 Y-------Y-------Y-------Y-------
129 Y-------Y-------Y-------Y-------
133 Y-------Y-------Y-------Y-------
137 Y-------Y-------Y-------Y-------
142 We use a resampling filter to shift the site locations one quarter pixel (at
143 the chroma plane's resolution) to the right.
144 The 4:2:2 modes look exactly the same, except there are twice as many chroma
145 lines, and they are vertically co-sited with the luma samples in both the
146 mpeg2 and jpeg cases (thus requiring no vertical resampling).*/
147 static void y4m_42xmpeg2_42xjpeg_helper(unsigned char *_dst
,
148 const unsigned char *_src
,int _c_w
,int _c_h
){
153 /*Filter: [4 -17 114 35 -9 1]/128, derived from a 6-tap Lanczos
155 for(x
=0;x
<OC_MINI(_c_w
,2);x
++){
156 _dst
[x
]=(unsigned char)OC_CLAMPI(0,(4*_src
[0]-17*_src
[OC_MAXI(x
-1,0)]+
157 114*_src
[x
]+35*_src
[OC_MINI(x
+1,_c_w
-1)]-9*_src
[OC_MINI(x
+2,_c_w
-1)]+
158 _src
[OC_MINI(x
+3,_c_w
-1)]+64)>>7,255);
161 _dst
[x
]=(unsigned char)OC_CLAMPI(0,(4*_src
[x
-2]-17*_src
[x
-1]+
162 114*_src
[x
]+35*_src
[x
+1]-9*_src
[x
+2]+_src
[x
+3]+64)>>7,255);
165 _dst
[x
]=(unsigned char)OC_CLAMPI(0,(4*_src
[x
-2]-17*_src
[x
-1]+
166 114*_src
[x
]+35*_src
[OC_MINI(x
+1,_c_w
-1)]-9*_src
[OC_MINI(x
+2,_c_w
-1)]+
167 _src
[_c_w
-1]+64)>>7,255);
174 /*Handles both 422 and 420mpeg2 to 422jpeg and 420jpeg, respectively.*/
175 static void y4m_convert_42xmpeg2_42xjpeg(y4m_input
*_y4m
,unsigned char *_dst
,
176 unsigned char *_aux
){
183 /*Skip past the luma data.*/
184 _dst
+=_y4m
->pic_w
*_y4m
->pic_h
;
185 /*Compute the size of each chroma plane.*/
186 c_w
=(_y4m
->pic_w
+_y4m
->dst_c_dec_h
-1)/_y4m
->dst_c_dec_h
;
187 c_h
=(_y4m
->pic_h
+_y4m
->dst_c_dec_v
-1)/_y4m
->dst_c_dec_v
;
189 for(pli
=1;pli
<3;pli
++){
190 y4m_42xmpeg2_42xjpeg_helper(_dst
,_aux
,c_w
,c_h
);
196 /*This format is only used for interlaced content, but is included for
199 420jpeg chroma samples are sited like:
200 Y-------Y-------Y-------Y-------
204 Y-------Y-------Y-------Y-------
208 Y-------Y-------Y-------Y-------
212 Y-------Y-------Y-------Y-------
217 420paldv chroma samples are sited like:
218 YR------Y-------YR------Y-------
222 YB------Y-------YB------Y-------
226 YR------Y-------YR------Y-------
230 YB------Y-------YB------Y-------
235 We use a resampling filter to shift the site locations one quarter pixel (at
236 the chroma plane's resolution) to the right.
237 Then we use another filter to move the C_r location down one quarter pixel,
238 and the C_b location up one quarter pixel.*/
239 static void y4m_convert_42xpaldv_42xjpeg(y4m_input
*_y4m
,unsigned char *_dst
,
240 unsigned char *_aux
){
248 /*Skip past the luma data.*/
249 _dst
+=_y4m
->pic_w
*_y4m
->pic_h
;
250 /*Compute the size of each chroma plane.*/
251 c_w
=(_y4m
->pic_w
+1)/2;
252 c_h
=(_y4m
->pic_h
+_y4m
->dst_c_dec_h
-1)/_y4m
->dst_c_dec_h
;
255 for(pli
=1;pli
<3;pli
++){
256 /*First do the horizontal re-sampling.
257 This is the same as the mpeg2 case, except that after the horizontal
258 case, we need to apply a second vertical filter.*/
259 y4m_42xmpeg2_42xjpeg_helper(tmp
,_aux
,c_w
,c_h
);
263 /*Slide C_b up a quarter-pel.
264 This is the same filter used above, but in the other order.*/
266 for(y
=0;y
<OC_MINI(c_h
,3);y
++){
267 _dst
[y
*c_w
]=(unsigned char)OC_CLAMPI(0,(tmp
[0]
268 -9*tmp
[OC_MAXI(y
-2,0)*c_w
]+35*tmp
[OC_MAXI(y
-1,0)*c_w
]
269 +114*tmp
[y
*c_w
]-17*tmp
[OC_MINI(y
+1,c_h
-1)*c_w
]
270 +4*tmp
[OC_MINI(y
+2,c_h
-1)*c_w
]+64)>>7,255);
273 _dst
[y
*c_w
]=(unsigned char)OC_CLAMPI(0,(tmp
[(y
-3)*c_w
]
274 -9*tmp
[(y
-2)*c_w
]+35*tmp
[(y
-1)*c_w
]+114*tmp
[y
*c_w
]
275 -17*tmp
[(y
+1)*c_w
]+4*tmp
[(y
+2)*c_w
]+64)>>7,255);
278 _dst
[y
*c_w
]=(unsigned char)OC_CLAMPI(0,(tmp
[(y
-3)*c_w
]
279 -9*tmp
[(y
-2)*c_w
]+35*tmp
[(y
-1)*c_w
]+114*tmp
[y
*c_w
]
280 -17*tmp
[OC_MINI(y
+1,c_h
-1)*c_w
]+4*tmp
[(c_h
-1)*c_w
]+64)>>7,255);
289 /*Slide C_r down a quarter-pel.
290 This is the same as the horizontal filter.*/
292 for(y
=0;y
<OC_MINI(c_h
,2);y
++){
293 _dst
[y
*c_w
]=(unsigned char)OC_CLAMPI(0,(4*tmp
[0]
294 -17*tmp
[OC_MAXI(y
-1,0)*c_w
]+114*tmp
[y
*c_w
]
295 +35*tmp
[OC_MINI(y
+1,c_h
-1)*c_w
]-9*tmp
[OC_MINI(y
+2,c_h
-1)*c_w
]
296 +tmp
[OC_MINI(y
+3,c_h
-1)*c_w
]+64)>>7,255);
299 _dst
[y
*c_w
]=(unsigned char)OC_CLAMPI(0,(4*tmp
[(y
-2)*c_w
]
300 -17*tmp
[(y
-1)*c_w
]+114*tmp
[y
*c_w
]+35*tmp
[(y
+1)*c_w
]
301 -9*tmp
[(y
+2)*c_w
]+tmp
[(y
+3)*c_w
]+64)>>7,255);
304 _dst
[y
*c_w
]=(unsigned char)OC_CLAMPI(0,(4*tmp
[(y
-2)*c_w
]
305 -17*tmp
[(y
-1)*c_w
]+114*tmp
[y
*c_w
]+35*tmp
[OC_MINI(y
+1,c_h
-1)*c_w
]
306 -9*tmp
[OC_MINI(y
+2,c_h
-1)*c_w
]+tmp
[(c_h
-1)*c_w
]+64)>>7,255);
313 /*For actual interlaced material, this would have to be done separately on
314 each field, and the shift amounts would be different.
315 C_r moves down 1/8, C_b up 3/8 in the top field, and C_r moves down 3/8,
316 C_b up 1/8 in the bottom field.
317 The corresponding filters would be:
318 Down 1/8 (reverse order for up): [3 -11 125 15 -4 0]/128
319 Down 3/8 (reverse order for up): [4 -19 98 56 -13 2]/128*/
323 /*Perform vertical filtering to reduce a single plane from 4:2:2 to 4:2:0.
324 This is used as a helper by several converation routines.*/
325 static void y4m_422jpeg_420jpeg_helper(unsigned char *_dst
,
326 const unsigned char *_src
,int _c_w
,int _c_h
){
329 /*Filter: [3 -17 78 78 -17 3]/128, derived from a 6-tap Lanczos window.*/
331 for(y
=0;y
<OC_MINI(_c_h
,2);y
+=2){
332 _dst
[(y
>>1)*_c_w
]=OC_CLAMPI(0,(64*_src
[0]
333 +78*_src
[OC_MINI(1,_c_h
-1)*_c_w
]
334 -17*_src
[OC_MINI(2,_c_h
-1)*_c_w
]
335 +3*_src
[OC_MINI(3,_c_h
-1)*_c_w
]+64)>>7,255);
338 _dst
[(y
>>1)*_c_w
]=OC_CLAMPI(0,(3*(_src
[(y
-2)*_c_w
]+_src
[(y
+3)*_c_w
])
339 -17*(_src
[(y
-1)*_c_w
]+_src
[(y
+2)*_c_w
])
340 +78*(_src
[y
*_c_w
]+_src
[(y
+1)*_c_w
])+64)>>7,255);
343 _dst
[(y
>>1)*_c_w
]=OC_CLAMPI(0,(3*(_src
[(y
-2)*_c_w
]
344 +_src
[(_c_h
-1)*_c_w
])-17*(_src
[(y
-1)*_c_w
]
345 +_src
[OC_MINI(y
+2,_c_h
-1)*_c_w
])
346 +78*(_src
[y
*_c_w
]+_src
[OC_MINI(y
+1,_c_h
-1)*_c_w
])+64)>>7,255);
353 /*420jpeg chroma samples are sited like:
354 Y-------Y-------Y-------Y-------
358 Y-------Y-------Y-------Y-------
362 Y-------Y-------Y-------Y-------
366 Y-------Y-------Y-------Y-------
371 422jpeg chroma samples are sited like:
372 Y---BR--Y-------Y---BR--Y-------
376 Y---BR--Y-------Y---BR--Y-------
380 Y---BR--Y-------Y---BR--Y-------
384 Y---BR--Y-------Y---BR--Y-------
389 We use a resampling filter to decimate the chroma planes by two in the
390 vertical direction.*/
391 static void y4m_convert_422jpeg_420jpeg(y4m_input
*_y4m
,unsigned char *_dst
,
392 unsigned char *_aux
){
402 /*Skip past the luma data.*/
403 _dst
+=_y4m
->pic_w
*_y4m
->pic_h
;
404 /*Compute the size of each chroma plane.*/
405 c_w
=(_y4m
->pic_w
+_y4m
->src_c_dec_h
-1)/_y4m
->src_c_dec_h
;
407 dst_c_w
=(_y4m
->pic_w
+_y4m
->dst_c_dec_h
-1)/_y4m
->dst_c_dec_h
;
408 dst_c_h
=(_y4m
->pic_h
+_y4m
->dst_c_dec_v
-1)/_y4m
->dst_c_dec_v
;
410 dst_c_sz
=dst_c_w
*dst_c_h
;
411 for(pli
=1;pli
<3;pli
++){
412 y4m_422jpeg_420jpeg_helper(_dst
,_aux
,c_w
,c_h
);
418 /*420jpeg chroma samples are sited like:
419 Y-------Y-------Y-------Y-------
423 Y-------Y-------Y-------Y-------
427 Y-------Y-------Y-------Y-------
431 Y-------Y-------Y-------Y-------
436 422 chroma samples are sited like:
437 YBR-----Y-------YBR-----Y-------
441 YBR-----Y-------YBR-----Y-------
445 YBR-----Y-------YBR-----Y-------
449 YBR-----Y-------YBR-----Y-------
454 We use a resampling filter to shift the original site locations one quarter
455 pixel (at the original chroma resolution) to the right.
456 Then we use a second resampling filter to decimate the chroma planes by two
457 in the vertical direction.*/
458 static void y4m_convert_422_420jpeg(y4m_input
*_y4m
,unsigned char *_dst
,
459 unsigned char *_aux
){
470 /*Skip past the luma data.*/
471 _dst
+=_y4m
->pic_w
*_y4m
->pic_h
;
472 /*Compute the size of each chroma plane.*/
473 c_w
=(_y4m
->pic_w
+_y4m
->src_c_dec_h
-1)/_y4m
->src_c_dec_h
;
475 dst_c_h
=(_y4m
->pic_h
+_y4m
->dst_c_dec_v
-1)/_y4m
->dst_c_dec_v
;
477 dst_c_sz
=c_w
*dst_c_h
;
479 for(pli
=1;pli
<3;pli
++){
480 /*In reality, the horizontal and vertical steps could be pipelined, for
481 less memory consumption and better cache performance, but we do them
482 separately for simplicity.*/
483 /*First do horizontal filtering (convert to 422jpeg)*/
484 y4m_42xmpeg2_42xjpeg_helper(tmp
,_aux
,c_w
,c_h
);
485 /*Now do the vertical filtering.*/
486 y4m_422jpeg_420jpeg_helper(_dst
,tmp
,c_w
,c_h
);
492 /*420jpeg chroma samples are sited like:
493 Y-------Y-------Y-------Y-------
497 Y-------Y-------Y-------Y-------
501 Y-------Y-------Y-------Y-------
505 Y-------Y-------Y-------Y-------
510 411 chroma samples are sited like:
511 YBR-----Y-------Y-------Y-------
515 YBR-----Y-------Y-------Y-------
519 YBR-----Y-------Y-------Y-------
523 YBR-----Y-------Y-------Y-------
528 We use a filter to resample at site locations one eighth pixel (at the source
529 chroma plane's horizontal resolution) and five eighths of a pixel to the
531 Then we use another filter to decimate the planes by 2 in the vertical
533 static void y4m_convert_411_420jpeg(y4m_input
*_y4m
,unsigned char *_dst
,
534 unsigned char *_aux
){
546 /*Skip past the luma data.*/
547 _dst
+=_y4m
->pic_w
*_y4m
->pic_h
;
548 /*Compute the size of each chroma plane.*/
549 c_w
=(_y4m
->pic_w
+_y4m
->src_c_dec_h
-1)/_y4m
->src_c_dec_h
;
551 dst_c_w
=(_y4m
->pic_w
+_y4m
->dst_c_dec_h
-1)/_y4m
->dst_c_dec_h
;
552 dst_c_h
=(_y4m
->pic_h
+_y4m
->dst_c_dec_v
-1)/_y4m
->dst_c_dec_v
;
554 dst_c_sz
=dst_c_w
*dst_c_h
;
557 for(pli
=1;pli
<3;pli
++){
558 /*In reality, the horizontal and vertical steps could be pipelined, for
559 less memory consumption and better cache performance, but we do them
560 separately for simplicity.*/
561 /*First do horizontal filtering (convert to 422jpeg)*/
563 /*Filters: [1 110 18 -1]/128 and [-3 50 86 -5]/128, both derived from a
564 4-tap Mitchell window.*/
565 for(x
=0;x
<OC_MINI(c_w
,1);x
++){
566 tmp
[x
<<1]=(unsigned char)OC_CLAMPI(0,(111*_aux
[0]
567 +18*_aux
[OC_MINI(1,c_w
-1)]-_aux
[OC_MINI(2,c_w
-1)]+64)>>7,255);
568 tmp
[x
<<1|1]=(unsigned char)OC_CLAMPI(0,(47*_aux
[0]
569 +86*_aux
[OC_MINI(1,c_w
-1)]-5*_aux
[OC_MINI(2,c_w
-1)]+64)>>7,255);
572 tmp
[x
<<1]=(unsigned char)OC_CLAMPI(0,(_aux
[x
-1]+110*_aux
[x
]
573 +18*_aux
[x
+1]-_aux
[x
+2]+64)>>7,255);
574 tmp
[x
<<1|1]=(unsigned char)OC_CLAMPI(0,(-3*_aux
[x
-1]+50*_aux
[x
]
575 +86*_aux
[x
+1]-5*_aux
[x
+2]+64)>>7,255);
578 tmp
[x
<<1]=(unsigned char)OC_CLAMPI(0,(_aux
[x
-1]+110*_aux
[x
]
579 +18*_aux
[OC_MINI(x
+1,c_w
-1)]-_aux
[c_w
-1]+64)>>7,255);
580 if((x
<<1|1)<dst_c_w
){
581 tmp
[x
<<1|1]=(unsigned char)OC_CLAMPI(0,(-3*_aux
[x
-1]+50*_aux
[x
]
582 +86*_aux
[OC_MINI(x
+1,c_w
-1)]-5*_aux
[c_w
-1]+64)>>7,255);
589 /*Now do the vertical filtering.*/
590 y4m_422jpeg_420jpeg_helper(_dst
,tmp
,dst_c_w
,c_h
);
595 /*Convert 444 to 420jpeg.*/
596 static void y4m_convert_444_420jpeg(y4m_input
*_y4m
,unsigned char *_dst
,
597 unsigned char *_aux
){
609 /*Skip past the luma data.*/
610 _dst
+=_y4m
->pic_w
*_y4m
->pic_h
;
611 /*Compute the size of each chroma plane.*/
612 c_w
=(_y4m
->pic_w
+_y4m
->src_c_dec_h
-1)/_y4m
->src_c_dec_h
;
614 dst_c_w
=(_y4m
->pic_w
+_y4m
->dst_c_dec_h
-1)/_y4m
->dst_c_dec_h
;
615 dst_c_h
=(_y4m
->pic_h
+_y4m
->dst_c_dec_v
-1)/_y4m
->dst_c_dec_v
;
617 dst_c_sz
=dst_c_w
*dst_c_h
;
620 for(pli
=1;pli
<3;pli
++){
621 /*Filter: [3 -17 78 78 -17 3]/128, derived from a 6-tap Lanczos window.*/
623 for(x
=0;x
<OC_MINI(c_w
,2);x
+=2){
624 tmp
[x
>>1]=OC_CLAMPI(0,(64*_aux
[0]+78*_aux
[OC_MINI(1,c_w
-1)]
625 -17*_aux
[OC_MINI(2,c_w
-1)]
626 +3*_aux
[OC_MINI(3,c_w
-1)]+64)>>7,255);
629 tmp
[x
>>1]=OC_CLAMPI(0,(3*(_aux
[x
-2]+_aux
[x
+3])
630 -17*(_aux
[x
-1]+_aux
[x
+2])+78*(_aux
[x
]+_aux
[x
+1])+64)>>7,255);
633 tmp
[x
>>1]=OC_CLAMPI(0,(3*(_aux
[x
-2]+_aux
[c_w
-1])-
634 17*(_aux
[x
-1]+_aux
[OC_MINI(x
+2,c_w
-1)])+
635 78*(_aux
[x
]+_aux
[OC_MINI(x
+1,c_w
-1)])+64)>>7,255);
641 /*Now do the vertical filtering.*/
642 y4m_422jpeg_420jpeg_helper(_dst
,tmp
,dst_c_w
,c_h
);
647 /*The image is padded with empty chroma components at 4:2:0.*/
648 static void y4m_convert_mono_420jpeg(y4m_input
*_y4m
,unsigned char *_dst
,
649 unsigned char *_aux
){
651 _dst
+=_y4m
->pic_w
*_y4m
->pic_h
;
652 c_sz
=((_y4m
->pic_w
+_y4m
->dst_c_dec_h
-1)/_y4m
->dst_c_dec_h
)*
653 ((_y4m
->pic_h
+_y4m
->dst_c_dec_v
-1)/_y4m
->dst_c_dec_v
);
654 memset(_dst
,128,c_sz
*2);
657 /*No conversion function needed.*/
658 static void y4m_convert_null(y4m_input
*_y4m
,unsigned char *_dst
,
659 unsigned char *_aux
){
662 int y4m_input_open(y4m_input
*_y4m
,FILE *_fin
,char *_skip
,int _nskip
){
666 /*Read until newline, or 80 cols, whichever happens first.*/
673 ret
=fread(buffer
+i
,1,1,_fin
);
676 if(buffer
[i
]=='\n')break;
678 /*We skipped too much header data.*/
679 if(_nskip
>0)return -1;
681 fprintf(stderr
,"Error parsing header; not a YUV2MPEG2 file?\n");
685 if(memcmp(buffer
,"YUV4MPEG",8)){
686 fprintf(stderr
,"Incomplete magic for YUV4MPEG file.\n");
690 fprintf(stderr
,"Incorrect YUV input file version; YUV4MPEG2 required.\n");
692 ret
=y4m_parse_tags(_y4m
,buffer
+5);
694 fprintf(stderr
,"Error parsing YUV4MPEG2 header.\n");
697 if(_y4m
->interlace
=='?'){
698 fprintf(stderr
,"Warning: Input video interlacing format unknown; "
699 "assuming progressive scan.\n");
701 else if(_y4m
->interlace
!='p'){
702 fprintf(stderr
,"Input video is interlaced; "
703 "Only progressive scan handled.\n");
706 if(strcmp(_y4m
->chroma_type
,"420")==0||
707 strcmp(_y4m
->chroma_type
,"420jpeg")==0){
708 _y4m
->src_c_dec_h
=_y4m
->dst_c_dec_h
=_y4m
->src_c_dec_v
=_y4m
->dst_c_dec_v
=2;
709 _y4m
->dst_buf_read_sz
=_y4m
->pic_w
*_y4m
->pic_h
710 +2*((_y4m
->pic_w
+1)/2)*((_y4m
->pic_h
+1)/2);
711 /*Natively supported: no conversion required.*/
712 _y4m
->aux_buf_sz
=_y4m
->aux_buf_read_sz
=0;
713 _y4m
->convert
=y4m_convert_null
;
715 else if(strcmp(_y4m
->chroma_type
,"420mpeg2")==0){
716 _y4m
->src_c_dec_h
=_y4m
->dst_c_dec_h
=_y4m
->src_c_dec_v
=_y4m
->dst_c_dec_v
=2;
717 _y4m
->dst_buf_read_sz
=_y4m
->pic_w
*_y4m
->pic_h
;
718 /*Chroma filter required: read into the aux buf first.*/
719 _y4m
->aux_buf_sz
=_y4m
->aux_buf_read_sz
=
720 2*((_y4m
->pic_w
+1)/2)*((_y4m
->pic_h
+1)/2);
721 _y4m
->convert
=y4m_convert_42xmpeg2_42xjpeg
;
723 else if(strcmp(_y4m
->chroma_type
,"420paldv")==0){
724 _y4m
->src_c_dec_h
=_y4m
->dst_c_dec_h
=_y4m
->src_c_dec_v
=_y4m
->dst_c_dec_v
=2;
725 _y4m
->dst_buf_read_sz
=_y4m
->pic_w
*_y4m
->pic_h
;
726 /*Chroma filter required: read into the aux buf first.
727 We need to make two filter passes, so we need some extra space in the
729 _y4m
->aux_buf_sz
=3*((_y4m
->pic_w
+1)/2)*((_y4m
->pic_h
+1)/2);
730 _y4m
->aux_buf_read_sz
=2*((_y4m
->pic_w
+1)/2)*((_y4m
->pic_h
+1)/2);
731 _y4m
->convert
=y4m_convert_42xpaldv_42xjpeg
;
733 else if(strcmp(_y4m
->chroma_type
,"422jpeg")==0){
734 _y4m
->src_c_dec_h
=_y4m
->dst_c_dec_h
=2;
737 _y4m
->dst_buf_read_sz
=_y4m
->pic_w
*_y4m
->pic_h
;
738 /*Chroma filter required: read into the aux buf first.*/
739 _y4m
->aux_buf_sz
=_y4m
->aux_buf_read_sz
=2*((_y4m
->pic_w
+1)/2)*_y4m
->pic_h
;
740 _y4m
->convert
=y4m_convert_422jpeg_420jpeg
;
742 else if(strcmp(_y4m
->chroma_type
,"422")==0){
743 _y4m
->src_c_dec_h
=_y4m
->dst_c_dec_h
=2;
746 _y4m
->dst_buf_read_sz
=_y4m
->pic_w
*_y4m
->pic_h
;
747 /*Chroma filter required: read into the aux buf first.
748 We need to make two filter passes, so we need some extra space in the
750 _y4m
->aux_buf_read_sz
=2*((_y4m
->pic_w
+1)/2)*_y4m
->pic_h
;
751 _y4m
->aux_buf_sz
=_y4m
->aux_buf_read_sz
+((_y4m
->pic_w
+1)/2)*_y4m
->pic_h
;
752 _y4m
->convert
=y4m_convert_422_420jpeg
;
754 else if(strcmp(_y4m
->chroma_type
,"411")==0){
759 _y4m
->dst_buf_read_sz
=_y4m
->pic_w
*_y4m
->pic_h
;
760 /*Chroma filter required: read into the aux buf first.
761 We need to make two filter passes, so we need some extra space in the
763 _y4m
->aux_buf_read_sz
=2*((_y4m
->pic_w
+3)/4)*_y4m
->pic_h
;
764 _y4m
->aux_buf_sz
=_y4m
->aux_buf_read_sz
+((_y4m
->pic_w
+1)/2)*_y4m
->pic_h
;
765 _y4m
->convert
=y4m_convert_411_420jpeg
;
767 else if(strcmp(_y4m
->chroma_type
,"444")==0){
772 _y4m
->dst_buf_read_sz
=_y4m
->pic_w
*_y4m
->pic_h
;
773 /*Chroma filter required: read into the aux buf first.
774 We need to make two filter passes, so we need some extra space in the
776 _y4m
->aux_buf_read_sz
=2*_y4m
->pic_w
*_y4m
->pic_h
;
777 _y4m
->aux_buf_sz
=_y4m
->aux_buf_read_sz
+((_y4m
->pic_w
+1)/2)*_y4m
->pic_h
;
778 _y4m
->convert
=y4m_convert_444_420jpeg
;
780 else if(strcmp(_y4m
->chroma_type
,"444alpha")==0){
785 _y4m
->dst_buf_read_sz
=_y4m
->pic_w
*_y4m
->pic_h
;
786 /*Chroma filter required: read into the aux buf first.
787 We need to make two filter passes, so we need some extra space in the
789 The extra plane also gets read into the aux buf.
790 It will be discarded.*/
791 _y4m
->aux_buf_sz
=_y4m
->aux_buf_read_sz
=3*_y4m
->pic_w
*_y4m
->pic_h
;
792 _y4m
->convert
=y4m_convert_444_420jpeg
;
794 else if(strcmp(_y4m
->chroma_type
,"mono")==0){
795 _y4m
->src_c_dec_h
=_y4m
->src_c_dec_v
=0;
796 _y4m
->dst_c_dec_h
=_y4m
->dst_c_dec_v
=2;
797 _y4m
->dst_buf_read_sz
=_y4m
->pic_w
*_y4m
->pic_h
;
798 /*No extra space required, but we need to clear the chroma planes.*/
799 _y4m
->aux_buf_sz
=_y4m
->aux_buf_read_sz
=0;
800 _y4m
->convert
=y4m_convert_mono_420jpeg
;
803 fprintf(stderr
,"Unknown chroma sampling type: %s\n",_y4m
->chroma_type
);
806 /*The size of the final frame buffers is always computed from the
807 destination chroma decimation type.*/
808 _y4m
->dst_buf_sz
=_y4m
->pic_w
*_y4m
->pic_h
809 +2*((_y4m
->pic_w
+_y4m
->dst_c_dec_h
-1)/_y4m
->dst_c_dec_h
)*
810 ((_y4m
->pic_h
+_y4m
->dst_c_dec_v
-1)/_y4m
->dst_c_dec_v
);
811 _y4m
->dst_buf
=(unsigned char *)malloc(_y4m
->dst_buf_sz
);
812 _y4m
->aux_buf
=(unsigned char *)malloc(_y4m
->aux_buf_sz
);
816 void y4m_input_close(y4m_input
*_y4m
){
821 int y4m_input_fetch_frame(y4m_input
*_y4m
,FILE *_fin
,vpx_image_t
*_img
){
830 /*Read and skip the frame header.*/
831 ret
=fread(frame
,1,6,_fin
);
833 if(memcmp(frame
,"FRAME",5)){
834 fprintf(stderr
,"Loss of framing in Y4M input data\n");
840 for(j
=0;j
<79&&fread(&c
,1,1,_fin
)&&c
!='\n';j
++);
842 fprintf(stderr
,"Error parsing Y4M frame header\n");
846 /*Read the frame data that needs no conversion.*/
847 if(fread(_y4m
->dst_buf
,1,_y4m
->dst_buf_read_sz
,_fin
)!=_y4m
->dst_buf_read_sz
){
848 fprintf(stderr
,"Error reading Y4M frame data.\n");
851 /*Read the frame data that does need conversion.*/
852 if(fread(_y4m
->aux_buf
,1,_y4m
->aux_buf_read_sz
,_fin
)!=_y4m
->aux_buf_read_sz
){
853 fprintf(stderr
,"Error reading Y4M frame data.\n");
856 /*Now convert the just read frame.*/
857 (*_y4m
->convert
)(_y4m
,_y4m
->dst_buf
,_y4m
->aux_buf
);
858 /*Fill in the frame buffer pointers.
859 We don't use vpx_img_wrap() because it forces padding for odd picture
860 sizes, which would require a separate fread call for every row.*/
861 memset(_img
,0,sizeof(*_img
));
862 /*Y4M has the planes in Y'CbCr order, which libvpx calls Y, U, and V.*/
863 _img
->fmt
=IMG_FMT_I420
;
864 _img
->w
=_img
->d_w
=_y4m
->pic_w
;
865 _img
->h
=_img
->d_h
=_y4m
->pic_h
;
866 /*This is hard-coded to 4:2:0 for now, as that's all VP8 supports.*/
867 _img
->x_chroma_shift
=1;
868 _img
->y_chroma_shift
=1;
870 /*Set up the buffer pointers.*/
871 pic_sz
=_y4m
->pic_w
*_y4m
->pic_h
;
872 c_w
=(_y4m
->pic_w
+_y4m
->dst_c_dec_h
-1)/_y4m
->dst_c_dec_h
;
873 c_h
=(_y4m
->pic_h
+_y4m
->dst_c_dec_v
-1)/_y4m
->dst_c_dec_v
;
875 _img
->stride
[PLANE_Y
]=_y4m
->pic_w
;
876 _img
->stride
[PLANE_U
]=_img
->stride
[PLANE_V
]=c_w
;
877 _img
->planes
[PLANE_Y
]=_y4m
->dst_buf
;
878 _img
->planes
[PLANE_U
]=_y4m
->dst_buf
+pic_sz
;
879 _img
->planes
[PLANE_V
]=_y4m
->dst_buf
+pic_sz
+c_sz
;