9a0ddd09 |
/*
* Interplay C93 video decoder
* Copyright (c) 2007 Anssi Hannula <anssi.hannula@gmail.com>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software |
e5a389a1 |
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
9a0ddd09 |
*/
#include "avcodec.h"
#include "bytestream.h" |
759001c5 |
#include "internal.h" |
9a0ddd09 |
typedef struct { |
670c7451 |
AVFrame *pictures[2]; |
9a0ddd09 |
int currentpic;
} C93DecoderContext;
typedef enum {
C93_8X8_FROM_PREV = 0x02,
C93_4X4_FROM_PREV = 0x06,
C93_4X4_FROM_CURR = 0x07,
C93_8X8_2COLOR = 0x08,
C93_4X4_2COLOR = 0x0A,
C93_4X4_4COLOR_GRP = 0x0B,
C93_4X4_4COLOR = 0x0D,
C93_NOOP = 0x0E,
C93_8X8_INTRA = 0x0F,
} C93BlockType;
#define WIDTH 320
#define HEIGHT 192
#define C93_HAS_PALETTE 0x01
#define C93_FIRST_FRAME 0x02
|
670c7451 |
static av_cold int decode_end(AVCodecContext *avctx) |
9a0ddd09 |
{ |
670c7451 |
C93DecoderContext * const c93 = avctx->priv_data;
av_frame_free(&c93->pictures[0]);
av_frame_free(&c93->pictures[1]);
|
9a0ddd09 |
return 0;
}
|
670c7451 |
static av_cold int decode_init(AVCodecContext *avctx) |
9a0ddd09 |
{ |
670c7451 |
C93DecoderContext *s = avctx->priv_data;
avctx->pix_fmt = AV_PIX_FMT_PAL8; |
9a0ddd09 |
|
670c7451 |
s->pictures[0] = av_frame_alloc();
s->pictures[1] = av_frame_alloc();
if (!s->pictures[0] || !s->pictures[1]) {
decode_end(avctx);
return AVERROR(ENOMEM);
} |
759001c5 |
|
9a0ddd09 |
return 0;
}
|
bee4f778 |
static inline int copy_block(AVCodecContext *avctx, uint8_t *to, |
9a0ddd09 |
uint8_t *from, int offset, int height, int stride)
{
int i;
int width = height;
int from_x = offset % WIDTH;
int from_y = offset / WIDTH;
int overflow = from_x + width - WIDTH;
if (!from) {
/* silently ignoring predictive blocks in first frame */
return 0;
}
if (from_y + height > HEIGHT) {
av_log(avctx, AV_LOG_ERROR, "invalid offset %d during C93 decoding\n",
offset); |
aadb7b3a |
return AVERROR_INVALIDDATA; |
9a0ddd09 |
}
if (overflow > 0) {
width -= overflow;
for (i = 0; i < height; i++) {
memcpy(&to[i*stride+width], &from[(from_y+i)*stride], overflow);
}
}
for (i = 0; i < height; i++) {
memcpy(&to[i*stride], &from[(from_y+i)*stride+from_x], width);
}
return 0;
}
|
bee4f778 |
static inline void draw_n_color(uint8_t *out, int stride, int width, |
9a0ddd09 |
int height, int bpp, uint8_t cols[4], uint8_t grps[4], uint32_t col)
{
int x, y;
for (y = 0; y < height; y++) {
if (grps)
cols[0] = grps[3 * (y >> 1)];
for (x = 0; x < width; x++) {
if (grps)
cols[1]= grps[(x >> 1) + 1];
out[x + y*stride] = cols[col & ((1 << bpp) - 1)];
col >>= bpp;
}
}
}
|
bee4f778 |
static int decode_frame(AVCodecContext *avctx, void *data, |
df9b9567 |
int *got_frame, AVPacket *avpkt) |
9a0ddd09 |
{ |
7a00bbad |
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size; |
9a0ddd09 |
C93DecoderContext * const c93 = avctx->priv_data; |
670c7451 |
AVFrame * const newpic = c93->pictures[c93->currentpic];
AVFrame * const oldpic = c93->pictures[c93->currentpic^1]; |
85aded74 |
GetByteContext gb; |
9a0ddd09 |
uint8_t *out; |
aadb7b3a |
int stride, ret, i, x, y, b, bt = 0; |
9a0ddd09 |
|
7722ae35 |
if ((ret = ff_set_dimensions(avctx, WIDTH, HEIGHT)) < 0)
return ret; |
4f1a17b1 |
|
9a0ddd09 |
c93->currentpic ^= 1;
|
1ec94b0f |
if ((ret = ff_reget_buffer(avctx, newpic)) < 0) |
aadb7b3a |
return ret; |
9a0ddd09 |
stride = newpic->linesize[0];
|
85aded74 |
bytestream2_init(&gb, buf, buf_size);
b = bytestream2_get_byte(&gb);
if (b & C93_FIRST_FRAME) { |
ce5e49b0 |
newpic->pict_type = AV_PICTURE_TYPE_I; |
9a0ddd09 |
newpic->key_frame = 1;
} else { |
ce5e49b0 |
newpic->pict_type = AV_PICTURE_TYPE_P; |
9a0ddd09 |
newpic->key_frame = 0;
}
for (y = 0; y < HEIGHT; y += 8) {
out = newpic->data[0] + y * stride;
for (x = 0; x < WIDTH; x += 8) {
uint8_t *copy_from = oldpic->data[0];
unsigned int offset, j;
uint8_t cols[4], grps[4]; |
fb12fca3 |
C93BlockType block_type; |
9a0ddd09 |
if (!bt) |
85aded74 |
bt = bytestream2_get_byte(&gb); |
9a0ddd09 |
|
fb12fca3 |
block_type= bt & 0x0F;
switch (block_type) { |
9a0ddd09 |
case C93_8X8_FROM_PREV: |
85aded74 |
offset = bytestream2_get_le16(&gb); |
11c3f204 |
if ((ret = copy_block(avctx, out, copy_from, offset, 8, stride)) < 0)
return ret; |
9a0ddd09 |
break;
case C93_4X4_FROM_CURR:
copy_from = newpic->data[0];
case C93_4X4_FROM_PREV:
for (j = 0; j < 8; j += 4) {
for (i = 0; i < 8; i += 4) { |
6b657ac7 |
int offset = bytestream2_get_le16(&gb);
int from_x = offset % WIDTH;
int from_y = offset / WIDTH;
if (block_type == C93_4X4_FROM_CURR && from_y == y+j &&
(FFABS(from_x - x-i) < 4 || FFABS(from_x - x-i) > WIDTH-4)) {
avpriv_request_sample(avctx, "block overlap %d %d %d %d\n", from_x, x+i, from_y, y+j);
return AVERROR_INVALIDDATA;
} |
11c3f204 |
if ((ret = copy_block(avctx, &out[j*stride+i],
copy_from, offset, 4, stride)) < 0)
return ret; |
9a0ddd09 |
}
}
break;
case C93_8X8_2COLOR: |
85aded74 |
bytestream2_get_buffer(&gb, cols, 2); |
9a0ddd09 |
for (i = 0; i < 8; i++) { |
bee4f778 |
draw_n_color(out + i*stride, stride, 8, 1, 1, cols, |
85aded74 |
NULL, bytestream2_get_byte(&gb)); |
9a0ddd09 |
}
break;
case C93_4X4_2COLOR:
case C93_4X4_4COLOR:
case C93_4X4_4COLOR_GRP:
for (j = 0; j < 8; j += 4) {
for (i = 0; i < 8; i += 4) { |
fb12fca3 |
if (block_type == C93_4X4_2COLOR) { |
85aded74 |
bytestream2_get_buffer(&gb, cols, 2); |
bee4f778 |
draw_n_color(out + i + j*stride, stride, 4, 4, |
85aded74 |
1, cols, NULL, bytestream2_get_le16(&gb)); |
fb12fca3 |
} else if (block_type == C93_4X4_4COLOR) { |
85aded74 |
bytestream2_get_buffer(&gb, cols, 4); |
bee4f778 |
draw_n_color(out + i + j*stride, stride, 4, 4, |
85aded74 |
2, cols, NULL, bytestream2_get_le32(&gb)); |
9a0ddd09 |
} else { |
85aded74 |
bytestream2_get_buffer(&gb, grps, 4); |
bee4f778 |
draw_n_color(out + i + j*stride, stride, 4, 4, |
85aded74 |
1, cols, grps, bytestream2_get_le16(&gb)); |
9a0ddd09 |
}
}
}
break;
case C93_NOOP:
break;
case C93_8X8_INTRA:
for (j = 0; j < 8; j++) |
85aded74 |
bytestream2_get_buffer(&gb, out + j*stride, 8); |
9a0ddd09 |
break;
default:
av_log(avctx, AV_LOG_ERROR, "unexpected type %x at %dx%d\n", |
fb12fca3 |
block_type, x, y); |
aadb7b3a |
return AVERROR_INVALIDDATA; |
9a0ddd09 |
}
bt >>= 4;
out += 8;
}
}
|
85aded74 |
if (b & C93_HAS_PALETTE) {
uint32_t *palette = (uint32_t *) newpic->data[1];
for (i = 0; i < 256; i++) { |
b25a265a |
palette[i] = 0xFFU << 24 | bytestream2_get_be24(&gb); |
85aded74 |
} |
f6e395e1 |
newpic->palette_has_changed = 1; |
85aded74 |
} else {
if (oldpic->data[1])
memcpy(newpic->data[1], oldpic->data[1], 256 * 4);
}
|
759001c5 |
if ((ret = av_frame_ref(data, newpic)) < 0)
return ret; |
df9b9567 |
*got_frame = 1; |
9a0ddd09 |
return buf_size;
}
|
e7e2df27 |
AVCodec ff_c93_decoder = { |
ec6402b7 |
.name = "c93", |
b2bed932 |
.long_name = NULL_IF_CONFIG_SMALL("Interplay C93"), |
ec6402b7 |
.type = AVMEDIA_TYPE_VIDEO, |
36ef5369 |
.id = AV_CODEC_ID_C93, |
ec6402b7 |
.priv_data_size = sizeof(C93DecoderContext),
.init = decode_init,
.close = decode_end,
.decode = decode_frame,
.capabilities = CODEC_CAP_DR1, |
9a0ddd09 |
}; |