2 * Interplay MVE Video Decoder
3 * Copyright (C) 2003 the ffmpeg project
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 * @file interplayvideo.c
25 * Interplay MVE Video Decoder by Mike Melanson (melanson@pcisys.net)
26 * For more information about the Interplay MVE format, visit:
27 * http://www.pcisys.net/~melanson/codecs/interplay-mve.txt
28 * This code is written in such a way that the identifiers match up
29 * with the encoding descriptions in the document.
31 * This decoder presently only supports a PAL8 output colorspace.
33 * An Interplay video frame consists of 2 parts: The decoding map and
34 * the video data. A demuxer must load these 2 parts together in a single
35 * buffer before sending it through the stream to this decoder.
44 #include "bytestream.h"
47 #define PALETTE_COUNT 256
49 /* debugging support */
50 #define DEBUG_INTERPLAY 0
52 #define debug_interplay(x,...) av_log(NULL, AV_LOG_DEBUG, x, __VA_ARGS__)
54 static inline void debug_interplay(const char *format, ...) { }
57 typedef struct IpvideoContext {
59 AVCodecContext *avctx;
61 AVFrame second_last_frame;
63 AVFrame current_frame;
64 unsigned char *decoding_map;
65 int decoding_map_size;
70 unsigned char *stream_ptr;
71 unsigned char *stream_end;
72 unsigned char *pixel_ptr;
75 int upper_motion_limit_offset;
79 #define CHECK_STREAM_PTR(n) \
80 if ((s->stream_ptr + n) > s->stream_end) { \
81 av_log(s->avctx, AV_LOG_ERROR, "Interplay video warning: stream_ptr out of bounds (%p >= %p)\n", \
82 s->stream_ptr + n, s->stream_end); \
86 #define COPY_FROM_CURRENT() \
87 motion_offset = current_offset; \
88 motion_offset += y * s->stride; \
90 if (motion_offset < 0) { \
91 av_log(s->avctx, AV_LOG_ERROR, " Interplay video: motion offset < 0 (%d)\n", motion_offset); \
93 } else if (motion_offset > s->upper_motion_limit_offset) { \
94 av_log(s->avctx, AV_LOG_ERROR, " Interplay video: motion offset above limit (%d >= %d)\n", \
95 motion_offset, s->upper_motion_limit_offset); \
98 s->dsp.put_pixels_tab[0][0](s->pixel_ptr, \
99 s->current_frame.data[0] + motion_offset, s->stride, 8);
101 #define COPY_FROM_PREVIOUS() \
102 motion_offset = current_offset; \
103 motion_offset += y * s->stride; \
104 motion_offset += x; \
105 if (motion_offset < 0) { \
106 av_log(s->avctx, AV_LOG_ERROR, " Interplay video: motion offset < 0 (%d)\n", motion_offset); \
108 } else if (motion_offset > s->upper_motion_limit_offset) { \
109 av_log(s->avctx, AV_LOG_ERROR, " Interplay video: motion offset above limit (%d >= %d)\n", \
110 motion_offset, s->upper_motion_limit_offset); \
113 s->dsp.put_pixels_tab[0][0](s->pixel_ptr, \
114 s->last_frame.data[0] + motion_offset, s->stride, 8);
116 #define COPY_FROM_SECOND_LAST() \
117 motion_offset = current_offset; \
118 motion_offset += y * s->stride; \
119 motion_offset += x; \
120 if (motion_offset < 0) { \
121 av_log(s->avctx, AV_LOG_ERROR, " Interplay video: motion offset < 0 (%d)\n", motion_offset); \
123 } else if (motion_offset > s->upper_motion_limit_offset) { \
124 av_log(s->avctx, AV_LOG_ERROR, " Interplay video: motion offset above limit (%d >= %d)\n", \
125 motion_offset, s->upper_motion_limit_offset); \
128 s->dsp.put_pixels_tab[0][0](s->pixel_ptr, \
129 s->second_last_frame.data[0] + motion_offset, s->stride, 8);
131 static int ipvideo_decode_block_opcode_0x0(IpvideoContext *s)
135 int current_offset = s->pixel_ptr - s->current_frame.data[0];
137 /* copy a block from the previous frame */
139 COPY_FROM_PREVIOUS();
145 static int ipvideo_decode_block_opcode_0x1(IpvideoContext *s)
149 int current_offset = s->pixel_ptr - s->current_frame.data[0];
151 /* copy block from 2 frames ago */
153 COPY_FROM_SECOND_LAST();
159 static int ipvideo_decode_block_opcode_0x2(IpvideoContext *s)
164 int current_offset = s->pixel_ptr - s->current_frame.data[0];
166 /* copy block from 2 frames ago using a motion vector; need 1 more byte */
168 B = *s->stream_ptr++;
174 x = -14 + ((B - 56) % 29);
175 y = 8 + ((B - 56) / 29);
178 debug_interplay (" motion byte = %d, (x, y) = (%d, %d)\n", B, x, y);
179 COPY_FROM_SECOND_LAST();
185 static int ipvideo_decode_block_opcode_0x3(IpvideoContext *s)
190 int current_offset = s->pixel_ptr - s->current_frame.data[0];
192 /* copy 8x8 block from current frame from an up/left block */
194 /* need 1 more byte for motion */
196 B = *s->stream_ptr++;
202 x = -(-14 + ((B - 56) % 29));
203 y = -( 8 + ((B - 56) / 29));
206 debug_interplay (" motion byte = %d, (x, y) = (%d, %d)\n", B, x, y);
213 static int ipvideo_decode_block_opcode_0x4(IpvideoContext *s)
216 unsigned char B, BL, BH;
218 int current_offset = s->pixel_ptr - s->current_frame.data[0];
220 /* copy a block from the previous frame; need 1 more byte */
223 B = *s->stream_ptr++;
225 BH = (B >> 4) & 0x0F;
229 debug_interplay (" motion byte = %d, (x, y) = (%d, %d)\n", B, x, y);
230 COPY_FROM_PREVIOUS();
236 static int ipvideo_decode_block_opcode_0x5(IpvideoContext *s)
240 int current_offset = s->pixel_ptr - s->current_frame.data[0];
242 /* copy a block from the previous frame using an expanded range;
243 * need 2 more bytes */
246 x = *s->stream_ptr++;
247 y = *s->stream_ptr++;
249 debug_interplay (" motion bytes = %d, %d\n", x, y);
250 COPY_FROM_PREVIOUS();
256 static int ipvideo_decode_block_opcode_0x6(IpvideoContext *s)
258 /* mystery opcode? skip multiple blocks? */
259 av_log(s->avctx, AV_LOG_ERROR, " Interplay video: Help! Mystery opcode 0x6 seen\n");
265 static int ipvideo_decode_block_opcode_0x7(IpvideoContext *s)
268 unsigned char P0, P1;
273 /* 2-color encoding */
276 P0 = *s->stream_ptr++;
277 P1 = *s->stream_ptr++;
281 /* need 8 more bytes from the stream */
283 for (y = 0; y < 8; y++)
284 B[y] = *s->stream_ptr++;
286 for (y = 0; y < 8; y++) {
288 for (x = 0x01; x <= 0x80; x <<= 1) {
290 *s->pixel_ptr++ = P1;
292 *s->pixel_ptr++ = P0;
294 s->pixel_ptr += s->line_inc;
299 /* need 2 more bytes from the stream */
302 flags = bytestream_get_le16(&s->stream_ptr);
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;
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;
326 static int ipvideo_decode_block_opcode_0x8(IpvideoContext *s)
331 unsigned int flags = 0;
332 unsigned int bitmask = 0;
333 unsigned char P0 = 0, P1 = 0;
336 /* 2-color encoding for each 4x4 quadrant, or 2-color encoding on
337 * either top and bottom or left and right halves */
340 P[0] = *s->stream_ptr++;
341 P[1] = *s->stream_ptr++;
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? */
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 */
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;
376 for (x = 0; x < 8; x++, bitmask <<= 1) {
377 /* get the pixel values ready for this quadrant */
379 P0 = P[lower_half + 0];
380 P1 = P[lower_half + 1];
382 P0 = P[lower_half + 4];
383 P1 = P[lower_half + 5];
387 *s->pixel_ptr++ = P1;
389 *s->pixel_ptr++ = P0;
391 s->pixel_ptr += s->line_inc;
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++;
406 /* vertical split; left & right halves are 2-color encoded */
408 for (y = 0; y < 8; y++) {
410 /* time to reload 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;
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 */
438 *s->pixel_ptr++ = P1;
440 *s->pixel_ptr++ = P0;
442 s->pixel_ptr += s->line_inc;
447 /* horizontal split; top & bottom halves are 2-color encoded */
449 for (y = 0; y < 8; y++) {
460 for (bitmask = 0x01; bitmask <= 0x80; bitmask <<= 1) {
463 *s->pixel_ptr++ = P1;
465 *s->pixel_ptr++ = P0;
467 s->pixel_ptr += s->line_inc;
476 static int ipvideo_decode_block_opcode_0x9(IpvideoContext *s)
480 unsigned int flags = 0;
484 /* 4-color encoding */
487 for (y = 0; y < 4; y++)
488 P[y] = *s->stream_ptr++;
490 if ((P[0] <= P[1]) && (P[2] <= P[3])) {
492 /* 1 of 4 colors for each pixel, need 16 more bytes */
493 CHECK_STREAM_PTR(16);
495 for (y = 0; y < 8; y++) {
496 /* get the next set of 8 2-bit flags */
497 flags = bytestream_get_le16(&s->stream_ptr);
498 for (x = 0, shifter = 0; x < 8; x++, shifter += 2) {
499 *s->pixel_ptr++ = P[(flags >> shifter) & 0x03];
501 s->pixel_ptr += s->line_inc;
504 } else if ((P[0] <= P[1]) && (P[2] > P[3])) {
506 /* 1 of 4 colors for each 2x2 block, need 4 more bytes */
509 flags = bytestream_get_le32(&s->stream_ptr);
512 for (y = 0; y < 8; y += 2) {
513 for (x = 0; x < 8; x += 2, shifter += 2) {
514 pix = P[(flags >> shifter) & 0x03];
515 *(s->pixel_ptr + x) = pix;
516 *(s->pixel_ptr + x + 1) = pix;
517 *(s->pixel_ptr + s->stride + x) = pix;
518 *(s->pixel_ptr + s->stride + x + 1) = pix;
520 s->pixel_ptr += s->stride * 2;
523 } else if ((P[0] > P[1]) && (P[2] <= P[3])) {
525 /* 1 of 4 colors for each 2x1 block, need 8 more bytes */
528 for (y = 0; y < 8; y++) {
529 /* time to reload flags? */
530 if ((y == 0) || (y == 4)) {
531 flags = bytestream_get_le32(&s->stream_ptr);
534 for (x = 0; x < 8; x += 2, shifter += 2) {
535 pix = P[(flags >> shifter) & 0x03];
536 *(s->pixel_ptr + x) = pix;
537 *(s->pixel_ptr + x + 1) = pix;
539 s->pixel_ptr += s->stride;
544 /* 1 of 4 colors for each 1x2 block, need 8 more bytes */
547 for (y = 0; y < 8; y += 2) {
548 /* time to reload flags? */
549 if ((y == 0) || (y == 4)) {
550 flags = bytestream_get_le32(&s->stream_ptr);
553 for (x = 0; x < 8; x++, shifter += 2) {
554 pix = P[(flags >> shifter) & 0x03];
555 *(s->pixel_ptr + x) = pix;
556 *(s->pixel_ptr + s->stride + x) = pix;
558 s->pixel_ptr += s->stride * 2;
566 static int ipvideo_decode_block_opcode_0xA(IpvideoContext *s)
577 /* 4-color encoding for each 4x4 quadrant, or 4-color encoding on
578 * either top and bottom or left and right halves */
581 for (y = 0; y < 4; y++)
582 P[y] = *s->stream_ptr++;
586 /* 4-color encoding for each quadrant; need 28 more bytes */
587 CHECK_STREAM_PTR(28);
589 for (y = 0; y < 4; y++)
590 B[y] = *s->stream_ptr++;
591 for (y = 4; y < 16; y += 4) {
592 for (x = y; x < y + 4; x++)
593 P[x] = *s->stream_ptr++;
594 for (x = y; x < y + 4; x++)
595 B[x] = *s->stream_ptr++;
598 for (y = 0; y < 8; y++) {
600 lower_half = (y >= 4) ? 4 : 0;
601 flags = (B[y + 8] << 8) | B[y];
603 for (x = 0, shifter = 0; x < 8; x++, shifter += 2) {
604 split = (x >= 4) ? 8 : 0;
605 index = split + lower_half + ((flags >> shifter) & 0x03);
606 *s->pixel_ptr++ = P[index];
609 s->pixel_ptr += s->line_inc;
614 /* 4-color encoding for either left and right or top and bottom
615 * halves; need 20 more bytes */
616 CHECK_STREAM_PTR(20);
618 for (y = 0; y < 8; y++)
619 B[y] = *s->stream_ptr++;
620 for (y = 4; y < 8; y++)
621 P[y] = *s->stream_ptr++;
622 for (y = 8; y < 16; y++)
623 B[y] = *s->stream_ptr++;
627 /* block is divided into left and right halves */
628 for (y = 0; y < 8; y++) {
630 flags = (B[y + 8] << 8) | B[y];
633 for (x = 0, shifter = 0; x < 8; x++, shifter += 2) {
636 *s->pixel_ptr++ = P[split + ((flags >> shifter) & 0x03)];
639 s->pixel_ptr += s->line_inc;
644 /* block is divided into top and bottom halves */
646 for (y = 0; y < 8; y++) {
648 flags = (B[y * 2 + 1] << 8) | B[y * 2];
652 for (x = 0, shifter = 0; x < 8; x++, shifter += 2)
653 *s->pixel_ptr++ = P[split + ((flags >> shifter) & 0x03)];
655 s->pixel_ptr += s->line_inc;
664 static int ipvideo_decode_block_opcode_0xB(IpvideoContext *s)
668 /* 64-color encoding (each pixel in block is a different color) */
669 CHECK_STREAM_PTR(64);
671 for (y = 0; y < 8; y++) {
672 for (x = 0; x < 8; x++) {
673 *s->pixel_ptr++ = *s->stream_ptr++;
675 s->pixel_ptr += s->line_inc;
682 static int ipvideo_decode_block_opcode_0xC(IpvideoContext *s)
687 /* 16-color block encoding: each 2x2 block is a different color */
688 CHECK_STREAM_PTR(16);
690 for (y = 0; y < 8; y += 2) {
691 for (x = 0; x < 8; x += 2) {
692 pix = *s->stream_ptr++;
693 *(s->pixel_ptr + x) = pix;
694 *(s->pixel_ptr + x + 1) = pix;
695 *(s->pixel_ptr + s->stride + x) = pix;
696 *(s->pixel_ptr + s->stride + x + 1) = pix;
698 s->pixel_ptr += s->stride * 2;
705 static int ipvideo_decode_block_opcode_0xD(IpvideoContext *s)
709 unsigned char index = 0;
711 /* 4-color block encoding: each 4x4 block is a different color */
714 for (y = 0; y < 4; y++)
715 P[y] = *s->stream_ptr++;
717 for (y = 0; y < 8; y++) {
723 for (x = 0; x < 8; x++) {
726 *s->pixel_ptr++ = P[index];
728 s->pixel_ptr += s->line_inc;
735 static int ipvideo_decode_block_opcode_0xE(IpvideoContext *s)
740 /* 1-color encoding: the whole block is 1 solid color */
742 pix = *s->stream_ptr++;
744 for (y = 0; y < 8; y++) {
745 for (x = 0; x < 8; x++) {
746 *s->pixel_ptr++ = pix;
748 s->pixel_ptr += s->line_inc;
755 static int ipvideo_decode_block_opcode_0xF(IpvideoContext *s)
758 unsigned char sample0, sample1;
760 /* dithered encoding */
762 sample0 = *s->stream_ptr++;
763 sample1 = *s->stream_ptr++;
765 for (y = 0; y < 8; y++) {
766 for (x = 0; x < 8; x += 2) {
768 *s->pixel_ptr++ = sample1;
769 *s->pixel_ptr++ = sample0;
771 *s->pixel_ptr++ = sample0;
772 *s->pixel_ptr++ = sample1;
775 s->pixel_ptr += s->line_inc;
782 static int (*ipvideo_decode_block[16])(IpvideoContext *s);
784 static void ipvideo_decode_opcodes(IpvideoContext *s)
788 unsigned char opcode;
791 static int frame = 0;
793 debug_interplay("------------------ frame %d\n", frame);
796 for (x = 0; x < 16; x++)
799 /* this is PAL8, so make the palette available */
800 memcpy(s->current_frame.data[1], s->avctx->palctrl->palette, PALETTE_COUNT * 4);
802 s->stride = s->current_frame.linesize[0];
803 s->stream_ptr = s->buf + 14; /* data starts 14 bytes in */
804 s->stream_end = s->buf + s->size;
805 s->line_inc = s->stride - 8;
806 s->upper_motion_limit_offset = (s->avctx->height - 8) * s->stride
807 + s->avctx->width - 8;
810 for (y = 0; y < (s->stride * s->avctx->height); y += s->stride * 8) {
811 for (x = y; x < y + s->avctx->width; x += 8) {
812 /* bottom nibble first, then top nibble (which makes it
813 * hard to use a GetBitcontext) */
815 opcode = s->decoding_map[index >> 1] >> 4;
817 opcode = s->decoding_map[index >> 1] & 0xF;
820 debug_interplay(" block @ (%3d, %3d): encoding 0x%X, data ptr @ %p\n",
821 x - y, y / s->stride, opcode, s->stream_ptr);
822 code_counts[opcode]++;
824 s->pixel_ptr = s->current_frame.data[0] + x;
825 ret = ipvideo_decode_block[opcode](s);
827 av_log(s->avctx, AV_LOG_ERROR, " Interplay video: decode problem on frame %d, @ block (%d, %d)\n",
828 frame, x - y, y / s->stride);
833 if ((s->stream_ptr != s->stream_end) &&
834 (s->stream_ptr + 1 != s->stream_end)) {
835 av_log(s->avctx, AV_LOG_ERROR, " Interplay video: decode finished with %td bytes left over\n",
836 s->stream_end - s->stream_ptr);
840 static int ipvideo_decode_init(AVCodecContext *avctx)
842 IpvideoContext *s = avctx->priv_data;
846 if (s->avctx->palctrl == NULL) {
847 av_log(avctx, AV_LOG_ERROR, " Interplay video: palette expected.\n");
851 avctx->pix_fmt = PIX_FMT_PAL8;
852 dsputil_init(&s->dsp, avctx);
854 /* decoding map contains 4 bits of information per 8x8 block */
855 s->decoding_map_size = avctx->width * avctx->height / (8 * 8 * 2);
857 /* assign block decode functions */
858 ipvideo_decode_block[0x0] = ipvideo_decode_block_opcode_0x0;
859 ipvideo_decode_block[0x1] = ipvideo_decode_block_opcode_0x1;
860 ipvideo_decode_block[0x2] = ipvideo_decode_block_opcode_0x2;
861 ipvideo_decode_block[0x3] = ipvideo_decode_block_opcode_0x3;
862 ipvideo_decode_block[0x4] = ipvideo_decode_block_opcode_0x4;
863 ipvideo_decode_block[0x5] = ipvideo_decode_block_opcode_0x5;
864 ipvideo_decode_block[0x6] = ipvideo_decode_block_opcode_0x6;
865 ipvideo_decode_block[0x7] = ipvideo_decode_block_opcode_0x7;
866 ipvideo_decode_block[0x8] = ipvideo_decode_block_opcode_0x8;
867 ipvideo_decode_block[0x9] = ipvideo_decode_block_opcode_0x9;
868 ipvideo_decode_block[0xA] = ipvideo_decode_block_opcode_0xA;
869 ipvideo_decode_block[0xB] = ipvideo_decode_block_opcode_0xB;
870 ipvideo_decode_block[0xC] = ipvideo_decode_block_opcode_0xC;
871 ipvideo_decode_block[0xD] = ipvideo_decode_block_opcode_0xD;
872 ipvideo_decode_block[0xE] = ipvideo_decode_block_opcode_0xE;
873 ipvideo_decode_block[0xF] = ipvideo_decode_block_opcode_0xF;
875 s->current_frame.data[0] = s->last_frame.data[0] =
876 s->second_last_frame.data[0] = NULL;
881 static int ipvideo_decode_frame(AVCodecContext *avctx,
882 void *data, int *data_size,
883 uint8_t *buf, int buf_size)
885 IpvideoContext *s = avctx->priv_data;
886 AVPaletteControl *palette_control = avctx->palctrl;
888 /* compressed buffer needs to be large enough to at least hold an entire
890 if (buf_size < s->decoding_map_size)
893 s->decoding_map = buf;
894 s->buf = buf + s->decoding_map_size;
895 s->size = buf_size - s->decoding_map_size;
897 s->current_frame.reference = 3;
898 if (avctx->get_buffer(avctx, &s->current_frame)) {
899 av_log(avctx, AV_LOG_ERROR, " Interplay Video: get_buffer() failed\n");
903 ipvideo_decode_opcodes(s);
905 if (palette_control->palette_changed) {
906 palette_control->palette_changed = 0;
907 s->current_frame.palette_has_changed = 1;
910 *data_size = sizeof(AVFrame);
911 *(AVFrame*)data = s->current_frame;
914 if (s->second_last_frame.data[0])
915 avctx->release_buffer(avctx, &s->second_last_frame);
916 s->second_last_frame = s->last_frame;
917 s->last_frame = s->current_frame;
918 s->current_frame.data[0] = NULL; /* catch any access attempts */
920 /* report that the buffer was completely consumed */
924 static int ipvideo_decode_end(AVCodecContext *avctx)
926 IpvideoContext *s = avctx->priv_data;
928 /* release the last frame */
929 if (s->last_frame.data[0])
930 avctx->release_buffer(avctx, &s->last_frame);
931 if (s->second_last_frame.data[0])
932 avctx->release_buffer(avctx, &s->second_last_frame);
937 AVCodec interplay_video_decoder = {
940 CODEC_ID_INTERPLAY_VIDEO,
941 sizeof(IpvideoContext),
945 ipvideo_decode_frame,