/* * 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);    }     av_frame_unref(s->prev_frame);    if ((ret = av_frame_ref(s->prev_frame, frame)) < 0)        return ret;     frame->pict_type = prev_pixels <= 0 ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;    frame->key_frame = prev_pixels <= 0;    *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,};