3 * Copyright (c) 2006 Konstantin Shishkov
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 * Karl Morton's Video Codec decoder
31 #include "bytestream.h"
33 #include "libavutil/common.h"
35 #define KMVC_KEYFRAME 0x80
36 #define KMVC_PALETTE 0x40
37 #define KMVC_METHOD 0x0F
38 #define MAX_PALSIZE 256
43 typedef struct KmvcContext
{
44 AVCodecContext
*avctx
;
48 uint32_t pal
[MAX_PALSIZE
];
50 uint8_t frm0
[320 * 200], frm1
[320 * 200];
54 typedef struct BitBuf
{
59 #define BLK(data, x, y) data[av_clip((x) + (y) * 320, 0, 320 * 200 -1)]
61 #define kmvc_init_getbits(bb, g) bb.bits = 7; bb.bitbuf = bytestream2_get_byte(g);
63 #define kmvc_getbit(bb, g, res) {\
65 if (bb.bitbuf & (1 << bb.bits)) res = 1; \
68 bb.bitbuf = bytestream2_get_byte(g); \
73 static int kmvc_decode_intra_8x8(KmvcContext
* ctx
, int w
, int h
)
79 int l0x
, l1x
, l0y
, l1y
;
82 kmvc_init_getbits(bb
, &ctx
->g
);
84 for (by
= 0; by
< h
; by
+= 8)
85 for (bx
= 0; bx
< w
; bx
+= 8) {
86 if (!bytestream2_get_bytes_left(&ctx
->g
)) {
87 av_log(ctx
->avctx
, AV_LOG_ERROR
, "Data overrun\n");
88 return AVERROR_INVALIDDATA
;
90 kmvc_getbit(bb
, &ctx
->g
, res
);
91 if (!res
) { // fill whole 8x8 block
92 val
= bytestream2_get_byte(&ctx
->g
);
93 for (i
= 0; i
< 64; i
++)
94 BLK(ctx
->cur
, bx
+ (i
& 0x7), by
+ (i
>> 3)) = val
;
95 } else { // handle four 4x4 subblocks
96 for (i
= 0; i
< 4; i
++) {
97 l0x
= bx
+ (i
& 1) * 4;
98 l0y
= by
+ (i
& 2) * 2;
99 kmvc_getbit(bb
, &ctx
->g
, res
);
101 kmvc_getbit(bb
, &ctx
->g
, res
);
102 if (!res
) { // fill whole 4x4 block
103 val
= bytestream2_get_byte(&ctx
->g
);
104 for (j
= 0; j
< 16; j
++)
105 BLK(ctx
->cur
, l0x
+ (j
& 3), l0y
+ (j
>> 2)) = val
;
106 } else { // copy block from already decoded place
107 val
= bytestream2_get_byte(&ctx
->g
);
110 if ((l0x
-mx
) + 320*(l0y
-my
) < 0 || (l0x
-mx
) + 320*(l0y
-my
) > 320*197 - 4) {
111 av_log(ctx
->avctx
, AV_LOG_ERROR
, "Invalid MV\n");
112 return AVERROR_INVALIDDATA
;
114 for (j
= 0; j
< 16; j
++)
115 BLK(ctx
->cur
, l0x
+ (j
& 3), l0y
+ (j
>> 2)) =
116 BLK(ctx
->cur
, l0x
+ (j
& 3) - mx
, l0y
+ (j
>> 2) - my
);
118 } else { // descend to 2x2 sub-sub-blocks
119 for (j
= 0; j
< 4; j
++) {
120 l1x
= l0x
+ (j
& 1) * 2;
122 kmvc_getbit(bb
, &ctx
->g
, res
);
124 kmvc_getbit(bb
, &ctx
->g
, res
);
125 if (!res
) { // fill whole 2x2 block
126 val
= bytestream2_get_byte(&ctx
->g
);
127 BLK(ctx
->cur
, l1x
, l1y
) = val
;
128 BLK(ctx
->cur
, l1x
+ 1, l1y
) = val
;
129 BLK(ctx
->cur
, l1x
, l1y
+ 1) = val
;
130 BLK(ctx
->cur
, l1x
+ 1, l1y
+ 1) = val
;
131 } else { // copy block from already decoded place
132 val
= bytestream2_get_byte(&ctx
->g
);
135 if ((l1x
-mx
) + 320*(l1y
-my
) < 0 || (l1x
-mx
) + 320*(l1y
-my
) > 320*199 - 2) {
136 av_log(ctx
->avctx
, AV_LOG_ERROR
, "Invalid MV\n");
137 return AVERROR_INVALIDDATA
;
139 BLK(ctx
->cur
, l1x
, l1y
) = BLK(ctx
->cur
, l1x
- mx
, l1y
- my
);
140 BLK(ctx
->cur
, l1x
+ 1, l1y
) =
141 BLK(ctx
->cur
, l1x
+ 1 - mx
, l1y
- my
);
142 BLK(ctx
->cur
, l1x
, l1y
+ 1) =
143 BLK(ctx
->cur
, l1x
- mx
, l1y
+ 1 - my
);
144 BLK(ctx
->cur
, l1x
+ 1, l1y
+ 1) =
145 BLK(ctx
->cur
, l1x
+ 1 - mx
, l1y
+ 1 - my
);
147 } else { // read values for block
148 BLK(ctx
->cur
, l1x
, l1y
) = bytestream2_get_byte(&ctx
->g
);
149 BLK(ctx
->cur
, l1x
+ 1, l1y
) = bytestream2_get_byte(&ctx
->g
);
150 BLK(ctx
->cur
, l1x
, l1y
+ 1) = bytestream2_get_byte(&ctx
->g
);
151 BLK(ctx
->cur
, l1x
+ 1, l1y
+ 1) = bytestream2_get_byte(&ctx
->g
);
162 static int kmvc_decode_inter_8x8(KmvcContext
* ctx
, int w
, int h
)
168 int l0x
, l1x
, l0y
, l1y
;
171 kmvc_init_getbits(bb
, &ctx
->g
);
173 for (by
= 0; by
< h
; by
+= 8)
174 for (bx
= 0; bx
< w
; bx
+= 8) {
175 kmvc_getbit(bb
, &ctx
->g
, res
);
177 kmvc_getbit(bb
, &ctx
->g
, res
);
178 if (!res
) { // fill whole 8x8 block
179 if (!bytestream2_get_bytes_left(&ctx
->g
)) {
180 av_log(ctx
->avctx
, AV_LOG_ERROR
, "Data overrun\n");
181 return AVERROR_INVALIDDATA
;
183 val
= bytestream2_get_byte(&ctx
->g
);
184 for (i
= 0; i
< 64; i
++)
185 BLK(ctx
->cur
, bx
+ (i
& 0x7), by
+ (i
>> 3)) = val
;
186 } else { // copy block from previous frame
187 for (i
= 0; i
< 64; i
++)
188 BLK(ctx
->cur
, bx
+ (i
& 0x7), by
+ (i
>> 3)) =
189 BLK(ctx
->prev
, bx
+ (i
& 0x7), by
+ (i
>> 3));
191 } else { // handle four 4x4 subblocks
192 if (!bytestream2_get_bytes_left(&ctx
->g
)) {
193 av_log(ctx
->avctx
, AV_LOG_ERROR
, "Data overrun\n");
194 return AVERROR_INVALIDDATA
;
196 for (i
= 0; i
< 4; i
++) {
197 l0x
= bx
+ (i
& 1) * 4;
198 l0y
= by
+ (i
& 2) * 2;
199 kmvc_getbit(bb
, &ctx
->g
, res
);
201 kmvc_getbit(bb
, &ctx
->g
, res
);
202 if (!res
) { // fill whole 4x4 block
203 val
= bytestream2_get_byte(&ctx
->g
);
204 for (j
= 0; j
< 16; j
++)
205 BLK(ctx
->cur
, l0x
+ (j
& 3), l0y
+ (j
>> 2)) = val
;
206 } else { // copy block
207 val
= bytestream2_get_byte(&ctx
->g
);
208 mx
= (val
& 0xF) - 8;
210 if ((l0x
+mx
) + 320*(l0y
+my
) < 0 || (l0x
+mx
) + 320*(l0y
+my
) > 320*197 - 4) {
211 av_log(ctx
->avctx
, AV_LOG_ERROR
, "Invalid MV\n");
212 return AVERROR_INVALIDDATA
;
214 for (j
= 0; j
< 16; j
++)
215 BLK(ctx
->cur
, l0x
+ (j
& 3), l0y
+ (j
>> 2)) =
216 BLK(ctx
->prev
, l0x
+ (j
& 3) + mx
, l0y
+ (j
>> 2) + my
);
218 } else { // descend to 2x2 sub-sub-blocks
219 for (j
= 0; j
< 4; j
++) {
220 l1x
= l0x
+ (j
& 1) * 2;
222 kmvc_getbit(bb
, &ctx
->g
, res
);
224 kmvc_getbit(bb
, &ctx
->g
, res
);
225 if (!res
) { // fill whole 2x2 block
226 val
= bytestream2_get_byte(&ctx
->g
);
227 BLK(ctx
->cur
, l1x
, l1y
) = val
;
228 BLK(ctx
->cur
, l1x
+ 1, l1y
) = val
;
229 BLK(ctx
->cur
, l1x
, l1y
+ 1) = val
;
230 BLK(ctx
->cur
, l1x
+ 1, l1y
+ 1) = val
;
231 } else { // copy block
232 val
= bytestream2_get_byte(&ctx
->g
);
233 mx
= (val
& 0xF) - 8;
235 if ((l1x
+mx
) + 320*(l1y
+my
) < 0 || (l1x
+mx
) + 320*(l1y
+my
) > 320*199 - 2) {
236 av_log(ctx
->avctx
, AV_LOG_ERROR
, "Invalid MV\n");
237 return AVERROR_INVALIDDATA
;
239 BLK(ctx
->cur
, l1x
, l1y
) = BLK(ctx
->prev
, l1x
+ mx
, l1y
+ my
);
240 BLK(ctx
->cur
, l1x
+ 1, l1y
) =
241 BLK(ctx
->prev
, l1x
+ 1 + mx
, l1y
+ my
);
242 BLK(ctx
->cur
, l1x
, l1y
+ 1) =
243 BLK(ctx
->prev
, l1x
+ mx
, l1y
+ 1 + my
);
244 BLK(ctx
->cur
, l1x
+ 1, l1y
+ 1) =
245 BLK(ctx
->prev
, l1x
+ 1 + mx
, l1y
+ 1 + my
);
247 } else { // read values for block
248 BLK(ctx
->cur
, l1x
, l1y
) = bytestream2_get_byte(&ctx
->g
);
249 BLK(ctx
->cur
, l1x
+ 1, l1y
) = bytestream2_get_byte(&ctx
->g
);
250 BLK(ctx
->cur
, l1x
, l1y
+ 1) = bytestream2_get_byte(&ctx
->g
);
251 BLK(ctx
->cur
, l1x
+ 1, l1y
+ 1) = bytestream2_get_byte(&ctx
->g
);
262 static int decode_frame(AVCodecContext
* avctx
, void *data
, int *got_frame
,
265 KmvcContext
*const ctx
= avctx
->priv_data
;
266 AVFrame
*frame
= data
;
271 const uint8_t *pal
= av_packet_get_side_data(avpkt
, AV_PKT_DATA_PALETTE
, NULL
);
273 bytestream2_init(&ctx
->g
, avpkt
->data
, avpkt
->size
);
275 if ((ret
= ff_get_buffer(avctx
, frame
, 0)) < 0)
278 header
= bytestream2_get_byte(&ctx
->g
);
280 /* blocksize 127 is really palette change event */
281 if (bytestream2_peek_byte(&ctx
->g
) == 127) {
282 bytestream2_skip(&ctx
->g
, 3);
283 for (i
= 0; i
< 127; i
++) {
284 ctx
->pal
[i
+ (header
& 0x81)] = 0xFFU
<< 24 | bytestream2_get_be24(&ctx
->g
);
285 bytestream2_skip(&ctx
->g
, 1);
287 bytestream2_seek(&ctx
->g
, -127 * 4 - 3, SEEK_CUR
);
290 if (header
& KMVC_KEYFRAME
) {
291 frame
->key_frame
= 1;
292 frame
->pict_type
= AV_PICTURE_TYPE_I
;
294 frame
->key_frame
= 0;
295 frame
->pict_type
= AV_PICTURE_TYPE_P
;
298 if (header
& KMVC_PALETTE
) {
299 frame
->palette_has_changed
= 1;
300 // palette starts from index 1 and has 127 entries
301 for (i
= 1; i
<= ctx
->palsize
; i
++) {
302 ctx
->pal
[i
] = 0xFFU
<< 24 | bytestream2_get_be24(&ctx
->g
);
307 frame
->palette_has_changed
= 1;
308 memcpy(ctx
->pal
, pal
, AVPALETTE_SIZE
);
313 frame
->palette_has_changed
= 1;
316 /* make the palette available on the way out */
317 memcpy(frame
->data
[1], ctx
->pal
, 1024);
319 blocksize
= bytestream2_get_byte(&ctx
->g
);
321 if (blocksize
!= 8 && blocksize
!= 127) {
322 av_log(avctx
, AV_LOG_ERROR
, "Block size = %i\n", blocksize
);
323 return AVERROR_INVALIDDATA
;
325 memset(ctx
->cur
, 0, 320 * 200);
326 switch (header
& KMVC_METHOD
) {
328 case 1: // used in palette changed event
329 memcpy(ctx
->cur
, ctx
->prev
, 320 * 200);
332 kmvc_decode_intra_8x8(ctx
, avctx
->width
, avctx
->height
);
335 kmvc_decode_inter_8x8(ctx
, avctx
->width
, avctx
->height
);
338 av_log(avctx
, AV_LOG_ERROR
, "Unknown compression method %i\n", header
& KMVC_METHOD
);
339 return AVERROR_INVALIDDATA
;
342 out
= frame
->data
[0];
344 for (i
= 0; i
< avctx
->height
; i
++) {
345 memcpy(out
, src
, avctx
->width
);
347 out
+= frame
->linesize
[0];
351 if (ctx
->cur
== ctx
->frm0
) {
352 ctx
->cur
= ctx
->frm1
;
353 ctx
->prev
= ctx
->frm0
;
355 ctx
->cur
= ctx
->frm0
;
356 ctx
->prev
= ctx
->frm1
;
361 /* always report that the buffer was completely consumed */
370 static av_cold
int decode_init(AVCodecContext
* avctx
)
372 KmvcContext
*const c
= avctx
->priv_data
;
377 if (avctx
->width
> 320 || avctx
->height
> 200) {
378 av_log(avctx
, AV_LOG_ERROR
, "KMVC supports frames <= 320x200\n");
379 return AVERROR(EINVAL
);
385 for (i
= 0; i
< 256; i
++) {
386 c
->pal
[i
] = 0xFFU
<< 24 | i
* 0x10101;
389 if (avctx
->extradata_size
< 12) {
390 av_log(avctx
, AV_LOG_WARNING
,
391 "Extradata missing, decoding may not work properly...\n");
394 c
->palsize
= AV_RL16(avctx
->extradata
+ 10);
395 if (c
->palsize
>= (unsigned)MAX_PALSIZE
) {
397 av_log(avctx
, AV_LOG_ERROR
, "KMVC palette too large\n");
398 return AVERROR_INVALIDDATA
;
402 if (avctx
->extradata_size
== 1036) { // palette in extradata
403 uint8_t *src
= avctx
->extradata
+ 12;
404 for (i
= 0; i
< 256; i
++) {
405 c
->pal
[i
] = AV_RL32(src
);
411 avctx
->pix_fmt
= AV_PIX_FMT_PAL8
;
416 AVCodec ff_kmvc_decoder
= {
418 .long_name
= NULL_IF_CONFIG_SMALL("Karl Morton's video codec"),
419 .type
= AVMEDIA_TYPE_VIDEO
,
420 .id
= AV_CODEC_ID_KMVC
,
421 .priv_data_size
= sizeof(KmvcContext
),
423 .decode
= decode_frame
,
424 .capabilities
= CODEC_CAP_DR1
,