Add undefine macro.
[plumiferos.git] / extern / ffmpeg / libavcodec / interplayvideo.c
blob73165e7950357d382f5a623e1bd4e75dfa59443d
1 /*
2 * Interplay MVE Video Decoder
3 * Copyright (C) 2003 the ffmpeg project
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 /**
22 * @file interplayvideo.c
23 * Interplay MVE Video Decoder by Mike Melanson (melanson@pcisys.net)
24 * For more information about the Interplay MVE format, visit:
25 * http://www.pcisys.net/~melanson/codecs/interplay-mve.txt
26 * This code is written in such a way that the identifiers match up
27 * with the encoding descriptions in the document.
29 * This decoder presently only supports a PAL8 output colorspace.
31 * An Interplay video frame consists of 2 parts: The decoding map and
32 * the video data. A demuxer must load these 2 parts together in a single
33 * buffer before sending it through the stream to this decoder.
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <string.h>
39 #include <unistd.h>
41 #include "common.h"
42 #include "avcodec.h"
43 #include "dsputil.h"
45 #define PALETTE_COUNT 256
47 /* debugging support */
48 #define DEBUG_INTERPLAY 0
49 #if DEBUG_INTERPLAY
50 #define debug_interplay(x,...) av_log(NULL, AV_LOG_DEBUG, x, __VA_ARGS__)
51 #else
52 static inline void debug_interplay(const char *format, ...) { }
53 #endif
55 typedef struct IpvideoContext {
57 AVCodecContext *avctx;
58 DSPContext dsp;
59 AVFrame second_last_frame;
60 AVFrame last_frame;
61 AVFrame current_frame;
62 unsigned char *decoding_map;
63 int decoding_map_size;
65 unsigned char *buf;
66 int size;
68 unsigned char *stream_ptr;
69 unsigned char *stream_end;
70 unsigned char *pixel_ptr;
71 int line_inc;
72 int stride;
73 int upper_motion_limit_offset;
75 } IpvideoContext;
77 #define CHECK_STREAM_PTR(n) \
78 if ((s->stream_ptr + n) > s->stream_end) { \
79 av_log(s->avctx, AV_LOG_ERROR, "Interplay video warning: stream_ptr out of bounds (%p >= %p)\n", \
80 s->stream_ptr + n, s->stream_end); \
81 return -1; \
84 #define COPY_FROM_CURRENT() \
85 motion_offset = current_offset; \
86 motion_offset += y * s->stride; \
87 motion_offset += x; \
88 if (motion_offset < 0) { \
89 av_log(s->avctx, AV_LOG_ERROR, " Interplay video: motion offset < 0 (%d)\n", motion_offset); \
90 return -1; \
91 } else if (motion_offset > s->upper_motion_limit_offset) { \
92 av_log(s->avctx, AV_LOG_ERROR, " Interplay video: motion offset above limit (%d >= %d)\n", \
93 motion_offset, s->upper_motion_limit_offset); \
94 return -1; \
95 } \
96 s->dsp.put_pixels_tab[0][0](s->pixel_ptr, \
97 s->current_frame.data[0] + motion_offset, s->stride, 8);
99 #define COPY_FROM_PREVIOUS() \
100 motion_offset = current_offset; \
101 motion_offset += y * s->stride; \
102 motion_offset += x; \
103 if (motion_offset < 0) { \
104 av_log(s->avctx, AV_LOG_ERROR, " Interplay video: motion offset < 0 (%d)\n", motion_offset); \
105 return -1; \
106 } else if (motion_offset > s->upper_motion_limit_offset) { \
107 av_log(s->avctx, AV_LOG_ERROR, " Interplay video: motion offset above limit (%d >= %d)\n", \
108 motion_offset, s->upper_motion_limit_offset); \
109 return -1; \
111 s->dsp.put_pixels_tab[0][0](s->pixel_ptr, \
112 s->last_frame.data[0] + motion_offset, s->stride, 8);
114 #define COPY_FROM_SECOND_LAST() \
115 motion_offset = current_offset; \
116 motion_offset += y * s->stride; \
117 motion_offset += x; \
118 if (motion_offset < 0) { \
119 av_log(s->avctx, AV_LOG_ERROR, " Interplay video: motion offset < 0 (%d)\n", motion_offset); \
120 return -1; \
121 } else if (motion_offset > s->upper_motion_limit_offset) { \
122 av_log(s->avctx, AV_LOG_ERROR, " Interplay video: motion offset above limit (%d >= %d)\n", \
123 motion_offset, s->upper_motion_limit_offset); \
124 return -1; \
126 s->dsp.put_pixels_tab[0][0](s->pixel_ptr, \
127 s->second_last_frame.data[0] + motion_offset, s->stride, 8);
129 static int ipvideo_decode_block_opcode_0x0(IpvideoContext *s)
131 int x, y;
132 int motion_offset;
133 int current_offset = s->pixel_ptr - s->current_frame.data[0];
135 /* copy a block from the previous frame */
136 x = y = 0;
137 COPY_FROM_PREVIOUS();
139 /* report success */
140 return 0;
143 static int ipvideo_decode_block_opcode_0x1(IpvideoContext *s)
145 int x, y;
146 int motion_offset;
147 int current_offset = s->pixel_ptr - s->current_frame.data[0];
149 /* copy block from 2 frames ago */
150 x = y = 0;
151 COPY_FROM_SECOND_LAST();
153 /* report success */
154 return 0;
157 static int ipvideo_decode_block_opcode_0x2(IpvideoContext *s)
159 unsigned char B;
160 int x, y;
161 int motion_offset;
162 int current_offset = s->pixel_ptr - s->current_frame.data[0];
164 /* copy block from 2 frames ago using a motion vector; need 1 more byte */
165 CHECK_STREAM_PTR(1);
166 B = *s->stream_ptr++;
168 if (B < 56) {
169 x = 8 + (B % 7);
170 y = B / 7;
171 } else {
172 x = -14 + ((B - 56) % 29);
173 y = 8 + ((B - 56) / 29);
176 debug_interplay (" motion byte = %d, (x, y) = (%d, %d)\n", B, x, y);
177 COPY_FROM_SECOND_LAST();
179 /* report success */
180 return 0;
183 static int ipvideo_decode_block_opcode_0x3(IpvideoContext *s)
185 unsigned char B;
186 int x, y;
187 int motion_offset;
188 int current_offset = s->pixel_ptr - s->current_frame.data[0];
190 /* copy 8x8 block from current frame from an up/left block */
192 /* need 1 more byte for motion */
193 CHECK_STREAM_PTR(1);
194 B = *s->stream_ptr++;
196 if (B < 56) {
197 x = -(8 + (B % 7));
198 y = -(B / 7);
199 } else {
200 x = -(-14 + ((B - 56) % 29));
201 y = -( 8 + ((B - 56) / 29));
204 debug_interplay (" motion byte = %d, (x, y) = (%d, %d)\n", B, x, y);
205 COPY_FROM_CURRENT();
207 /* report success */
208 return 0;
211 static int ipvideo_decode_block_opcode_0x4(IpvideoContext *s)
213 int x, y;
214 unsigned char B, BL, BH;
215 int motion_offset;
216 int current_offset = s->pixel_ptr - s->current_frame.data[0];
218 /* copy a block from the previous frame; need 1 more byte */
219 CHECK_STREAM_PTR(1);
221 B = *s->stream_ptr++;
222 BL = B & 0x0F;
223 BH = (B >> 4) & 0x0F;
224 x = -8 + BL;
225 y = -8 + BH;
227 debug_interplay (" motion byte = %d, (x, y) = (%d, %d)\n", B, x, y);
228 COPY_FROM_PREVIOUS();
230 /* report success */
231 return 0;
234 static int ipvideo_decode_block_opcode_0x5(IpvideoContext *s)
236 signed char x, y;
237 int motion_offset;
238 int current_offset = s->pixel_ptr - s->current_frame.data[0];
240 /* copy a block from the previous frame using an expanded range;
241 * need 2 more bytes */
242 CHECK_STREAM_PTR(2);
244 x = *s->stream_ptr++;
245 y = *s->stream_ptr++;
247 debug_interplay (" motion bytes = %d, %d\n", x, y);
248 COPY_FROM_PREVIOUS();
250 /* report success */
251 return 0;
254 static int ipvideo_decode_block_opcode_0x6(IpvideoContext *s)
256 /* mystery opcode? skip multiple blocks? */
257 av_log(s->avctx, AV_LOG_ERROR, " Interplay video: Help! Mystery opcode 0x6 seen\n");
259 /* report success */
260 return 0;
263 static int ipvideo_decode_block_opcode_0x7(IpvideoContext *s)
265 int x, y;
266 unsigned char P0, P1;
267 unsigned char B[8];
268 unsigned int flags;
269 int bitmask;
271 /* 2-color encoding */
272 CHECK_STREAM_PTR(2);
274 P0 = *s->stream_ptr++;
275 P1 = *s->stream_ptr++;
277 if (P0 <= P1) {
279 /* need 8 more bytes from the stream */
280 CHECK_STREAM_PTR(8);
281 for (y = 0; y < 8; y++)
282 B[y] = *s->stream_ptr++;
284 for (y = 0; y < 8; y++) {
285 flags = B[y];
286 for (x = 0x01; x <= 0x80; x <<= 1) {
287 if (flags & x)
288 *s->pixel_ptr++ = P1;
289 else
290 *s->pixel_ptr++ = P0;
292 s->pixel_ptr += s->line_inc;
295 } else {
297 /* need 2 more bytes from the stream */
298 CHECK_STREAM_PTR(2);
299 B[0] = *s->stream_ptr++;
300 B[1] = *s->stream_ptr++;
302 flags = (B[1] << 8) | B[0];
303 bitmask = 0x0001;
304 for (y = 0; y < 8; y += 2) {
305 for (x = 0; x < 8; x += 2, bitmask <<= 1) {
306 if (flags & bitmask) {
307 *(s->pixel_ptr + x) = P1;
308 *(s->pixel_ptr + x + 1) = P1;
309 *(s->pixel_ptr + s->stride + x) = P1;
310 *(s->pixel_ptr + s->stride + x + 1) = P1;
311 } else {
312 *(s->pixel_ptr + x) = P0;
313 *(s->pixel_ptr + x + 1) = P0;
314 *(s->pixel_ptr + s->stride + x) = P0;
315 *(s->pixel_ptr + s->stride + x + 1) = P0;
318 s->pixel_ptr += s->stride * 2;
322 /* report success */
323 return 0;
326 static int ipvideo_decode_block_opcode_0x8(IpvideoContext *s)
328 int x, y;
329 unsigned char P[8];
330 unsigned char B[8];
331 unsigned int flags = 0;
332 unsigned int bitmask = 0;
333 unsigned char P0 = 0, P1 = 0;
334 int lower_half = 0;
336 /* 2-color encoding for each 4x4 quadrant, or 2-color encoding on
337 * either top and bottom or left and right halves */
338 CHECK_STREAM_PTR(2);
340 P[0] = *s->stream_ptr++;
341 P[1] = *s->stream_ptr++;
343 if (P[0] <= P[1]) {
345 /* need 12 more bytes */
346 CHECK_STREAM_PTR(12);
347 B[0] = *s->stream_ptr++; B[1] = *s->stream_ptr++;
348 P[2] = *s->stream_ptr++; P[3] = *s->stream_ptr++;
349 B[2] = *s->stream_ptr++; B[3] = *s->stream_ptr++;
350 P[4] = *s->stream_ptr++; P[5] = *s->stream_ptr++;
351 B[4] = *s->stream_ptr++; B[5] = *s->stream_ptr++;
352 P[6] = *s->stream_ptr++; P[7] = *s->stream_ptr++;
353 B[6] = *s->stream_ptr++; B[7] = *s->stream_ptr++;
355 for (y = 0; y < 8; y++) {
357 /* time to reload flags? */
358 if (y == 0) {
359 flags =
360 ((B[0] & 0xF0) << 4) | ((B[4] & 0xF0) << 8) |
361 ((B[0] & 0x0F) ) | ((B[4] & 0x0F) << 4) |
362 ((B[1] & 0xF0) << 20) | ((B[5] & 0xF0) << 24) |
363 ((B[1] & 0x0F) << 16) | ((B[5] & 0x0F) << 20);
364 bitmask = 0x00000001;
365 lower_half = 0; /* still on top half */
366 } else if (y == 4) {
367 flags =
368 ((B[2] & 0xF0) << 4) | ((B[6] & 0xF0) << 8) |
369 ((B[2] & 0x0F) ) | ((B[6] & 0x0F) << 4) |
370 ((B[3] & 0xF0) << 20) | ((B[7] & 0xF0) << 24) |
371 ((B[3] & 0x0F) << 16) | ((B[7] & 0x0F) << 20);
372 bitmask = 0x00000001;
373 lower_half = 2;
376 for (x = 0; x < 8; x++, bitmask <<= 1) {
377 /* get the pixel values ready for this quadrant */
378 if (x == 0) {
379 P0 = P[lower_half + 0];
380 P1 = P[lower_half + 1];
381 } else if (x == 4) {
382 P0 = P[lower_half + 4];
383 P1 = P[lower_half + 5];
386 if (flags & bitmask)
387 *s->pixel_ptr++ = P1;
388 else
389 *s->pixel_ptr++ = P0;
391 s->pixel_ptr += s->line_inc;
394 } else {
396 /* need 10 more bytes */
397 CHECK_STREAM_PTR(10);
398 B[0] = *s->stream_ptr++; B[1] = *s->stream_ptr++;
399 B[2] = *s->stream_ptr++; B[3] = *s->stream_ptr++;
400 P[2] = *s->stream_ptr++; P[3] = *s->stream_ptr++;
401 B[4] = *s->stream_ptr++; B[5] = *s->stream_ptr++;
402 B[6] = *s->stream_ptr++; B[7] = *s->stream_ptr++;
404 if (P[2] <= P[3]) {
406 /* vertical split; left & right halves are 2-color encoded */
408 for (y = 0; y < 8; y++) {
410 /* time to reload flags? */
411 if (y == 0) {
412 flags =
413 ((B[0] & 0xF0) << 4) | ((B[4] & 0xF0) << 8) |
414 ((B[0] & 0x0F) ) | ((B[4] & 0x0F) << 4) |
415 ((B[1] & 0xF0) << 20) | ((B[5] & 0xF0) << 24) |
416 ((B[1] & 0x0F) << 16) | ((B[5] & 0x0F) << 20);
417 bitmask = 0x00000001;
418 } else if (y == 4) {
419 flags =
420 ((B[2] & 0xF0) << 4) | ((B[6] & 0xF0) << 8) |
421 ((B[2] & 0x0F) ) | ((B[6] & 0x0F) << 4) |
422 ((B[3] & 0xF0) << 20) | ((B[7] & 0xF0) << 24) |
423 ((B[3] & 0x0F) << 16) | ((B[7] & 0x0F) << 20);
424 bitmask = 0x00000001;
427 for (x = 0; x < 8; x++, bitmask <<= 1) {
428 /* get the pixel values ready for this half */
429 if (x == 0) {
430 P0 = P[0];
431 P1 = P[1];
432 } else if (x == 4) {
433 P0 = P[2];
434 P1 = P[3];
437 if (flags & bitmask)
438 *s->pixel_ptr++ = P1;
439 else
440 *s->pixel_ptr++ = P0;
442 s->pixel_ptr += s->line_inc;
445 } else {
447 /* horizontal split; top & bottom halves are 2-color encoded */
449 for (y = 0; y < 8; y++) {
451 flags = B[y];
452 if (y == 0) {
453 P0 = P[0];
454 P1 = P[1];
455 } else if (y == 4) {
456 P0 = P[2];
457 P1 = P[3];
460 for (bitmask = 0x01; bitmask <= 0x80; bitmask <<= 1) {
462 if (flags & bitmask)
463 *s->pixel_ptr++ = P1;
464 else
465 *s->pixel_ptr++ = P0;
467 s->pixel_ptr += s->line_inc;
472 /* report success */
473 return 0;
476 static int ipvideo_decode_block_opcode_0x9(IpvideoContext *s)
478 int x, y;
479 unsigned char P[4];
480 unsigned char B[4];
481 unsigned int flags = 0;
482 int shifter = 0;
483 unsigned char pix;
485 /* 4-color encoding */
486 CHECK_STREAM_PTR(4);
488 for (y = 0; y < 4; y++)
489 P[y] = *s->stream_ptr++;
491 if ((P[0] <= P[1]) && (P[2] <= P[3])) {
493 /* 1 of 4 colors for each pixel, need 16 more bytes */
494 CHECK_STREAM_PTR(16);
496 for (y = 0; y < 8; y++) {
497 /* get the next set of 8 2-bit flags */
498 flags = (s->stream_ptr[1] << 8) | s->stream_ptr[0];
499 s->stream_ptr += 2;
500 for (x = 0, shifter = 0; x < 8; x++, shifter += 2) {
501 *s->pixel_ptr++ = P[(flags >> shifter) & 0x03];
503 s->pixel_ptr += s->line_inc;
506 } else if ((P[0] <= P[1]) && (P[2] > P[3])) {
508 /* 1 of 4 colors for each 2x2 block, need 4 more bytes */
509 CHECK_STREAM_PTR(4);
511 B[0] = *s->stream_ptr++;
512 B[1] = *s->stream_ptr++;
513 B[2] = *s->stream_ptr++;
514 B[3] = *s->stream_ptr++;
515 flags = (B[3] << 24) | (B[2] << 16) | (B[1] << 8) | B[0];
516 shifter = 0;
518 for (y = 0; y < 8; y += 2) {
519 for (x = 0; x < 8; x += 2, shifter += 2) {
520 pix = P[(flags >> shifter) & 0x03];
521 *(s->pixel_ptr + x) = pix;
522 *(s->pixel_ptr + x + 1) = pix;
523 *(s->pixel_ptr + s->stride + x) = pix;
524 *(s->pixel_ptr + s->stride + x + 1) = pix;
526 s->pixel_ptr += s->stride * 2;
529 } else if ((P[0] > P[1]) && (P[2] <= P[3])) {
531 /* 1 of 4 colors for each 2x1 block, need 8 more bytes */
532 CHECK_STREAM_PTR(8);
534 for (y = 0; y < 8; y++) {
535 /* time to reload flags? */
536 if ((y == 0) || (y == 4)) {
537 B[0] = *s->stream_ptr++;
538 B[1] = *s->stream_ptr++;
539 B[2] = *s->stream_ptr++;
540 B[3] = *s->stream_ptr++;
541 flags = (B[3] << 24) | (B[2] << 16) | (B[1] << 8) | B[0];
542 shifter = 0;
544 for (x = 0; x < 8; x += 2, shifter += 2) {
545 pix = P[(flags >> shifter) & 0x03];
546 *(s->pixel_ptr + x) = pix;
547 *(s->pixel_ptr + x + 1) = pix;
549 s->pixel_ptr += s->stride;
552 } else {
554 /* 1 of 4 colors for each 1x2 block, need 8 more bytes */
555 CHECK_STREAM_PTR(8);
557 for (y = 0; y < 8; y += 2) {
558 /* time to reload flags? */
559 if ((y == 0) || (y == 4)) {
560 B[0] = *s->stream_ptr++;
561 B[1] = *s->stream_ptr++;
562 B[2] = *s->stream_ptr++;
563 B[3] = *s->stream_ptr++;
564 flags = (B[3] << 24) | (B[2] << 16) | (B[1] << 8) | B[0];
565 shifter = 0;
567 for (x = 0; x < 8; x++, shifter += 2) {
568 pix = P[(flags >> shifter) & 0x03];
569 *(s->pixel_ptr + x) = pix;
570 *(s->pixel_ptr + s->stride + x) = pix;
572 s->pixel_ptr += s->stride * 2;
576 /* report success */
577 return 0;
580 static int ipvideo_decode_block_opcode_0xA(IpvideoContext *s)
582 int x, y;
583 unsigned char P[16];
584 unsigned char B[16];
585 int flags = 0;
586 int shifter = 0;
587 int index;
588 int split;
589 int lower_half;
591 /* 4-color encoding for each 4x4 quadrant, or 4-color encoding on
592 * either top and bottom or left and right halves */
593 CHECK_STREAM_PTR(4);
595 for (y = 0; y < 4; y++)
596 P[y] = *s->stream_ptr++;
598 if (P[0] <= P[1]) {
600 /* 4-color encoding for each quadrant; need 28 more bytes */
601 CHECK_STREAM_PTR(28);
603 for (y = 0; y < 4; y++)
604 B[y] = *s->stream_ptr++;
605 for (y = 4; y < 16; y += 4) {
606 for (x = y; x < y + 4; x++)
607 P[x] = *s->stream_ptr++;
608 for (x = y; x < y + 4; x++)
609 B[x] = *s->stream_ptr++;
612 for (y = 0; y < 8; y++) {
614 lower_half = (y >= 4) ? 4 : 0;
615 flags = (B[y + 8] << 8) | B[y];
617 for (x = 0, shifter = 0; x < 8; x++, shifter += 2) {
618 split = (x >= 4) ? 8 : 0;
619 index = split + lower_half + ((flags >> shifter) & 0x03);
620 *s->pixel_ptr++ = P[index];
623 s->pixel_ptr += s->line_inc;
626 } else {
628 /* 4-color encoding for either left and right or top and bottom
629 * halves; need 20 more bytes */
630 CHECK_STREAM_PTR(20);
632 for (y = 0; y < 8; y++)
633 B[y] = *s->stream_ptr++;
634 for (y = 4; y < 8; y++)
635 P[y] = *s->stream_ptr++;
636 for (y = 8; y < 16; y++)
637 B[y] = *s->stream_ptr++;
639 if (P[4] <= P[5]) {
641 /* block is divided into left and right halves */
642 for (y = 0; y < 8; y++) {
644 flags = (B[y + 8] << 8) | B[y];
645 split = 0;
647 for (x = 0, shifter = 0; x < 8; x++, shifter += 2) {
648 if (x == 4)
649 split = 4;
650 *s->pixel_ptr++ = P[split + ((flags >> shifter) & 0x03)];
653 s->pixel_ptr += s->line_inc;
656 } else {
658 /* block is divided into top and bottom halves */
659 split = 0;
660 for (y = 0; y < 8; y++) {
662 flags = (B[y * 2 + 1] << 8) | B[y * 2];
663 if (y == 4)
664 split = 4;
666 for (x = 0, shifter = 0; x < 8; x++, shifter += 2)
667 *s->pixel_ptr++ = P[split + ((flags >> shifter) & 0x03)];
669 s->pixel_ptr += s->line_inc;
674 /* report success */
675 return 0;
678 static int ipvideo_decode_block_opcode_0xB(IpvideoContext *s)
680 int x, y;
682 /* 64-color encoding (each pixel in block is a different color) */
683 CHECK_STREAM_PTR(64);
685 for (y = 0; y < 8; y++) {
686 for (x = 0; x < 8; x++) {
687 *s->pixel_ptr++ = *s->stream_ptr++;
689 s->pixel_ptr += s->line_inc;
692 /* report success */
693 return 0;
696 static int ipvideo_decode_block_opcode_0xC(IpvideoContext *s)
698 int x, y;
699 unsigned char pix;
701 /* 16-color block encoding: each 2x2 block is a different color */
702 CHECK_STREAM_PTR(16);
704 for (y = 0; y < 8; y += 2) {
705 for (x = 0; x < 8; x += 2) {
706 pix = *s->stream_ptr++;
707 *(s->pixel_ptr + x) = pix;
708 *(s->pixel_ptr + x + 1) = pix;
709 *(s->pixel_ptr + s->stride + x) = pix;
710 *(s->pixel_ptr + s->stride + x + 1) = pix;
712 s->pixel_ptr += s->stride * 2;
715 /* report success */
716 return 0;
719 static int ipvideo_decode_block_opcode_0xD(IpvideoContext *s)
721 int x, y;
722 unsigned char P[4];
723 unsigned char index = 0;
725 /* 4-color block encoding: each 4x4 block is a different color */
726 CHECK_STREAM_PTR(4);
728 for (y = 0; y < 4; y++)
729 P[y] = *s->stream_ptr++;
731 for (y = 0; y < 8; y++) {
732 if (y < 4)
733 index = 0;
734 else
735 index = 2;
737 for (x = 0; x < 8; x++) {
738 if (x == 4)
739 index++;
740 *s->pixel_ptr++ = P[index];
742 s->pixel_ptr += s->line_inc;
745 /* report success */
746 return 0;
749 static int ipvideo_decode_block_opcode_0xE(IpvideoContext *s)
751 int x, y;
752 unsigned char pix;
754 /* 1-color encoding: the whole block is 1 solid color */
755 CHECK_STREAM_PTR(1);
756 pix = *s->stream_ptr++;
758 for (y = 0; y < 8; y++) {
759 for (x = 0; x < 8; x++) {
760 *s->pixel_ptr++ = pix;
762 s->pixel_ptr += s->line_inc;
765 /* report success */
766 return 0;
769 static int ipvideo_decode_block_opcode_0xF(IpvideoContext *s)
771 int x, y;
772 unsigned char sample0, sample1;
774 /* dithered encoding */
775 CHECK_STREAM_PTR(2);
776 sample0 = *s->stream_ptr++;
777 sample1 = *s->stream_ptr++;
779 for (y = 0; y < 8; y++) {
780 for (x = 0; x < 8; x += 2) {
781 if (y & 1) {
782 *s->pixel_ptr++ = sample1;
783 *s->pixel_ptr++ = sample0;
784 } else {
785 *s->pixel_ptr++ = sample0;
786 *s->pixel_ptr++ = sample1;
789 s->pixel_ptr += s->line_inc;
792 /* report success */
793 return 0;
796 static int (*ipvideo_decode_block[16])(IpvideoContext *s);
798 static void ipvideo_decode_opcodes(IpvideoContext *s)
800 int x, y;
801 int index = 0;
802 unsigned char opcode;
803 int ret;
804 int code_counts[16];
805 static int frame = 0;
807 debug_interplay("------------------ frame %d\n", frame);
808 frame++;
810 for (x = 0; x < 16; x++)
811 code_counts[x] = 0;
813 /* this is PAL8, so make the palette available */
814 memcpy(s->current_frame.data[1], s->avctx->palctrl->palette, PALETTE_COUNT * 4);
816 s->stride = s->current_frame.linesize[0];
817 s->stream_ptr = s->buf + 14; /* data starts 14 bytes in */
818 s->stream_end = s->buf + s->size;
819 s->line_inc = s->stride - 8;
820 s->upper_motion_limit_offset = (s->avctx->height - 8) * s->stride
821 + s->avctx->width - 8;
822 s->dsp = s->dsp;
824 for (y = 0; y < (s->stride * s->avctx->height); y += s->stride * 8) {
825 for (x = y; x < y + s->avctx->width; x += 8) {
826 /* bottom nibble first, then top nibble (which makes it
827 * hard to use a GetBitcontext) */
828 if (index & 1)
829 opcode = s->decoding_map[index >> 1] >> 4;
830 else
831 opcode = s->decoding_map[index >> 1] & 0xF;
832 index++;
834 debug_interplay(" block @ (%3d, %3d): encoding 0x%X, data ptr @ %p\n",
835 x - y, y / s->stride, opcode, s->stream_ptr);
836 code_counts[opcode]++;
838 s->pixel_ptr = s->current_frame.data[0] + x;
839 ret = ipvideo_decode_block[opcode](s);
840 if (ret != 0) {
841 av_log(s->avctx, AV_LOG_ERROR, " Interplay video: decode problem on frame %d, @ block (%d, %d)\n",
842 frame, x - y, y / s->stride);
843 return;
847 if ((s->stream_ptr != s->stream_end) &&
848 (s->stream_ptr + 1 != s->stream_end)) {
849 av_log(s->avctx, AV_LOG_ERROR, " Interplay video: decode finished with %td bytes left over\n",
850 s->stream_end - s->stream_ptr);
854 static int ipvideo_decode_init(AVCodecContext *avctx)
856 IpvideoContext *s = avctx->priv_data;
858 s->avctx = avctx;
860 if (s->avctx->palctrl == NULL) {
861 av_log(avctx, AV_LOG_ERROR, " Interplay video: palette expected.\n");
862 return -1;
865 avctx->pix_fmt = PIX_FMT_PAL8;
866 avctx->has_b_frames = 0;
867 dsputil_init(&s->dsp, avctx);
869 /* decoding map contains 4 bits of information per 8x8 block */
870 s->decoding_map_size = avctx->width * avctx->height / (8 * 8 * 2);
872 /* assign block decode functions */
873 ipvideo_decode_block[0x0] = ipvideo_decode_block_opcode_0x0;
874 ipvideo_decode_block[0x1] = ipvideo_decode_block_opcode_0x1;
875 ipvideo_decode_block[0x2] = ipvideo_decode_block_opcode_0x2;
876 ipvideo_decode_block[0x3] = ipvideo_decode_block_opcode_0x3;
877 ipvideo_decode_block[0x4] = ipvideo_decode_block_opcode_0x4;
878 ipvideo_decode_block[0x5] = ipvideo_decode_block_opcode_0x5;
879 ipvideo_decode_block[0x6] = ipvideo_decode_block_opcode_0x6;
880 ipvideo_decode_block[0x7] = ipvideo_decode_block_opcode_0x7;
881 ipvideo_decode_block[0x8] = ipvideo_decode_block_opcode_0x8;
882 ipvideo_decode_block[0x9] = ipvideo_decode_block_opcode_0x9;
883 ipvideo_decode_block[0xA] = ipvideo_decode_block_opcode_0xA;
884 ipvideo_decode_block[0xB] = ipvideo_decode_block_opcode_0xB;
885 ipvideo_decode_block[0xC] = ipvideo_decode_block_opcode_0xC;
886 ipvideo_decode_block[0xD] = ipvideo_decode_block_opcode_0xD;
887 ipvideo_decode_block[0xE] = ipvideo_decode_block_opcode_0xE;
888 ipvideo_decode_block[0xF] = ipvideo_decode_block_opcode_0xF;
890 s->current_frame.data[0] = s->last_frame.data[0] =
891 s->second_last_frame.data[0] = NULL;
893 return 0;
896 static int ipvideo_decode_frame(AVCodecContext *avctx,
897 void *data, int *data_size,
898 uint8_t *buf, int buf_size)
900 IpvideoContext *s = avctx->priv_data;
901 AVPaletteControl *palette_control = avctx->palctrl;
903 /* compressed buffer needs to be large enough to at least hold an entire
904 * decoding map */
905 if (buf_size < s->decoding_map_size)
906 return buf_size;
908 s->decoding_map = buf;
909 s->buf = buf + s->decoding_map_size;
910 s->size = buf_size - s->decoding_map_size;
912 s->current_frame.reference = 3;
913 if (avctx->get_buffer(avctx, &s->current_frame)) {
914 av_log(avctx, AV_LOG_ERROR, " Interplay Video: get_buffer() failed\n");
915 return -1;
918 ipvideo_decode_opcodes(s);
920 if (palette_control->palette_changed) {
921 palette_control->palette_changed = 0;
922 s->current_frame.palette_has_changed = 1;
925 *data_size = sizeof(AVFrame);
926 *(AVFrame*)data = s->current_frame;
928 /* shuffle frames */
929 if (s->second_last_frame.data[0])
930 avctx->release_buffer(avctx, &s->second_last_frame);
931 s->second_last_frame = s->last_frame;
932 s->last_frame = s->current_frame;
933 s->current_frame.data[0] = NULL; /* catch any access attempts */
935 /* report that the buffer was completely consumed */
936 return buf_size;
939 static int ipvideo_decode_end(AVCodecContext *avctx)
941 IpvideoContext *s = avctx->priv_data;
943 /* release the last frame */
944 if (s->last_frame.data[0])
945 avctx->release_buffer(avctx, &s->last_frame);
946 if (s->second_last_frame.data[0])
947 avctx->release_buffer(avctx, &s->second_last_frame);
949 return 0;
952 AVCodec interplay_video_decoder = {
953 "interplayvideo",
954 CODEC_TYPE_VIDEO,
955 CODEC_ID_INTERPLAY_VIDEO,
956 sizeof(IpvideoContext),
957 ipvideo_decode_init,
958 NULL,
959 ipvideo_decode_end,
960 ipvideo_decode_frame,
961 CODEC_CAP_DR1,