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/*
* Gryphon's Anim Compressor decoder
* Copyright (c) 2019 Paul B Mahol
*
* 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
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/internal.h"
#include "libavutil/intreadwrite.h"
#include "avcodec.h"
#include "bytestream.h"
#include "codec_internal.h"
#include "decode.h"
typedef struct ARBCContext {
GetByteContext gb;
AVFrame *prev_frame;
} ARBCContext;
static int fill_tile4(AVCodecContext *avctx, int color, AVFrame *frame)
{
ARBCContext *s = avctx->priv_data;
GetByteContext *gb = &s->gb;
int nb_tiles = bytestream2_get_le16(gb);
int h = avctx->height - 1;
int pixels_overwritten = 0;
if ((avctx->width / 4 + 1) * (avctx->height / 4 + 1) < nb_tiles)
return 0;
for (int i = 0; i < nb_tiles; i++) {
int y = bytestream2_get_byte(gb);
int x = bytestream2_get_byte(gb);
uint16_t mask = bytestream2_get_le16(gb);
int start_y = y * 4, start_x = x * 4;
int end_y = start_y + 4, end_x = start_x + 4;
for (int j = start_y; j < end_y; j++) {
for (int k = start_x; k < end_x; k++) {
if (mask & 0x8000) {
if (j >= avctx->height || k >= avctx->width) {
mask = mask << 1;
continue;
}
AV_WB24(&frame->data[0][frame->linesize[0] * (h - j) + 3 * k], color);
pixels_overwritten ++;
}
mask = mask << 1;
}
}
}
return pixels_overwritten;
}
static int fill_tileX(AVCodecContext *avctx, int tile_width, int tile_height,
int color, AVFrame *frame)
{
ARBCContext *s = avctx->priv_data;
GetByteContext *gb = &s->gb;
const int step_h = tile_height / 4;
const int step_w = tile_width / 4;
int nb_tiles = bytestream2_get_le16(gb);
int h = avctx->height - 1;
int pixels_overwritten = 0;
if ((avctx->width / tile_width + 1) * (avctx->height / tile_height + 1) < nb_tiles)
return 0;
for (int i = 0; i < nb_tiles; i++) {
int y = bytestream2_get_byte(gb);
int x = bytestream2_get_byte(gb);
uint16_t mask = bytestream2_get_le16(gb);
int start_y = y * tile_height, start_x = x * tile_width;
int end_y = start_y + tile_height, end_x = start_x + tile_width;
if (start_x >= avctx->width || start_y >= avctx->height)
continue;
for (int j = start_y; j < end_y; j += step_h) {
for (int k = start_x; k < end_x; k += step_w) {
if (mask & 0x8000U) {
for (int m = 0; m < step_h; m++) {
for (int n = 0; n < step_w; n++) {
if (j + m >= avctx->height || k + n >= avctx->width)
continue;
AV_WB24(&frame->data[0][frame->linesize[0] * (h - (j + m)) + 3 * (k + n)], color);
}
}
pixels_overwritten += FFMIN(step_h, avctx->height - j) * FFMIN(step_w, avctx->width - k);
}
mask = mask << 1;
}
}
}
return pixels_overwritten;
}
static int decode_frame(AVCodecContext *avctx, AVFrame *frame,
int *got_frame, AVPacket *avpkt)
{
ARBCContext *s = avctx->priv_data;
int ret, nb_segments;
int prev_pixels = avctx->width * avctx->height;
if (avpkt->size < 10)
return AVERROR_INVALIDDATA;
bytestream2_init(&s->gb, avpkt->data, avpkt->size);
bytestream2_skip(&s->gb, 8);
nb_segments = bytestream2_get_le16(&s->gb);
if (nb_segments == 0)
return avpkt->size;
if (7 * nb_segments > bytestream2_get_bytes_left(&s->gb))
return AVERROR_INVALIDDATA;
if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
return ret;
if (s->prev_frame->data[0]) {
ret = av_frame_copy(frame, s->prev_frame);
if (ret < 0)
return ret;
}
for (int i = 0; i < nb_segments; i++) {
int resolution_flag;
int fill;
if (bytestream2_get_bytes_left(&s->gb) <= 0)
return AVERROR_INVALIDDATA;
fill = bytestream2_get_byte(&s->gb) << 16;
bytestream2_skip(&s->gb, 1);
fill |= bytestream2_get_byte(&s->gb) << 8;
bytestream2_skip(&s->gb, 1);
fill |= bytestream2_get_byte(&s->gb) << 0;
bytestream2_skip(&s->gb, 1);
resolution_flag = bytestream2_get_byte(&s->gb);
if (resolution_flag & 0x10)
prev_pixels -= fill_tileX(avctx, 1024, 1024, fill, frame);
if (resolution_flag & 0x08)
prev_pixels -= fill_tileX(avctx, 256, 256, fill, frame);
if (resolution_flag & 0x04)
prev_pixels -= fill_tileX(avctx, 64, 64, fill, frame);
if (resolution_flag & 0x02)
prev_pixels -= fill_tileX(avctx, 16, 16, fill, frame);
if (resolution_flag & 0x01)
prev_pixels -= fill_tile4(avctx, fill, frame);
}
if ((ret = av_frame_replace(s->prev_frame, frame)) < 0)
return ret;
frame->pict_type = prev_pixels <= 0 ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
if (prev_pixels <= 0)
frame->flags |= AV_FRAME_FLAG_KEY;
else
frame->flags &= ~AV_FRAME_FLAG_KEY;
*got_frame = 1;
return avpkt->size;
}
static av_cold int decode_init(AVCodecContext *avctx)
{
ARBCContext *s = avctx->priv_data;
avctx->pix_fmt = AV_PIX_FMT_RGB24;
s->prev_frame = av_frame_alloc();
if (!s->prev_frame)
return AVERROR(ENOMEM);
return 0;
}
static void decode_flush(AVCodecContext *avctx)
{
ARBCContext *s = avctx->priv_data;
av_frame_unref(s->prev_frame);
}
static av_cold int decode_close(AVCodecContext *avctx)
{
ARBCContext *s = avctx->priv_data;
av_frame_free(&s->prev_frame);
return 0;
}
const FFCodec ff_arbc_decoder = {
.p.name = "arbc",
CODEC_LONG_NAME("Gryphon's Anim Compressor"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_ARBC,
.priv_data_size = sizeof(ARBCContext),
.init = decode_init,
FF_CODEC_DECODE_CB(decode_frame),
.flush = decode_flush,
.close = decode_close,
.p.capabilities = AV_CODEC_CAP_DR1,
.caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
};
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