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GCC Code Coverage Report

Directory:	../../../ffmpeg/		Exec	Total	Coverage
File:	src/libavcodec/cdgraphics.c	Lines:	98	176	55.7 %
Date:	2020-01-27 20:17:04	Branches:	37	89	41.6 %


/*
 * CD Graphics Video Decoder
 * Copyright (c) 2009 Michael Tison
 *
 * 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 "avcodec.h"
#include "bytestream.h"
#include "internal.h"

/**
 * @file
 * @brief CD Graphics Video Decoder
 * @author Michael Tison
 * @see http://wiki.multimedia.cx/index.php?title=CD_Graphics
 * @see http://www.ccs.neu.edu/home/bchafy/cdb/info/cdg
 */

/// default screen sizes
#define CDG_FULL_WIDTH           300
#define CDG_FULL_HEIGHT          216
#define CDG_DISPLAY_WIDTH        294
#define CDG_DISPLAY_HEIGHT       204
#define CDG_BORDER_WIDTH           6
#define CDG_BORDER_HEIGHT         12

/// masks
#define CDG_COMMAND             0x09
#define CDG_MASK                0x3F

/// instruction codes
#define CDG_INST_MEMORY_PRESET     1
#define CDG_INST_BORDER_PRESET     2
#define CDG_INST_TILE_BLOCK        6
#define CDG_INST_SCROLL_PRESET    20
#define CDG_INST_SCROLL_COPY      24
#define CDG_INST_TRANSPARENT_COL  28
#define CDG_INST_LOAD_PAL_LO      30
#define CDG_INST_LOAD_PAL_HIGH    31
#define CDG_INST_TILE_BLOCK_XOR   38

/// data sizes
#define CDG_PACKET_SIZE           24
#define CDG_DATA_SIZE             16
#define CDG_TILE_HEIGHT           12
#define CDG_TILE_WIDTH             6
#define CDG_MINIMUM_PKT_SIZE       6
#define CDG_MINIMUM_SCROLL_SIZE    3
#define CDG_HEADER_SIZE            8
#define CDG_PALETTE_SIZE          16

typedef struct CDGraphicsContext {
    AVFrame *frame;
    int hscroll;
    int vscroll;
    int transparency;
    int cleared;
} CDGraphicsContext;

static av_cold int cdg_decode_init(AVCodecContext *avctx)
{
    CDGraphicsContext *cc = avctx->priv_data;

    cc->frame = av_frame_alloc();
    if (!cc->frame)
        return AVERROR(ENOMEM);
    cc->transparency = -1;

    avctx->pix_fmt = AV_PIX_FMT_PAL8;
    return ff_set_dimensions(avctx, CDG_FULL_WIDTH, CDG_FULL_HEIGHT);
}

static void cdg_border_preset(CDGraphicsContext *cc, uint8_t *data)
{
    int y;
    int lsize    = cc->frame->linesize[0];
    uint8_t *buf = cc->frame->data[0];
    int color    = data[0] & 0x0F;

    if (!(data[1] & 0x0F)) {
        /// fill the top and bottom borders
        memset(buf, color, CDG_BORDER_HEIGHT * lsize);
        memset(buf + (CDG_FULL_HEIGHT - CDG_BORDER_HEIGHT) * lsize,
               color, CDG_BORDER_HEIGHT * lsize);

        /// fill the side borders
        for (y = CDG_BORDER_HEIGHT; y < CDG_FULL_HEIGHT - CDG_BORDER_HEIGHT; y++) {
            memset(buf + y * lsize, color, CDG_BORDER_WIDTH);
            memset(buf + CDG_FULL_WIDTH - CDG_BORDER_WIDTH + y * lsize,
                   color, CDG_BORDER_WIDTH);
        }
    }
}

static void cdg_load_palette(CDGraphicsContext *cc, uint8_t *data, int low)
{
    uint8_t r, g, b;
    uint16_t color;
    int i;
    int array_offset  = low ? 0 : 8;
    uint32_t *palette = (uint32_t *) cc->frame->data[1];

    for (i = 0; i < 8; i++) {
        color = (data[2 * i] << 6) + (data[2 * i + 1] & 0x3F);
        r = ((color >> 8) & 0x000F) * 17;
        g = ((color >> 4) & 0x000F) * 17;
        b = ((color     ) & 0x000F) * 17;
        palette[i + array_offset] = 0xFFU << 24 | r << 16 | g << 8 | b;
        if (cc->transparency >= 0)
            palette[cc->transparency] &= 0xFFFFFF;
    }
    cc->frame->palette_has_changed = 1;
}

static int cdg_tile_block(CDGraphicsContext *cc, uint8_t *data, int b)
{
    unsigned ci, ri;
    int color;
    int x, y;
    int ai;
    int stride   = cc->frame->linesize[0];
    uint8_t *buf = cc->frame->data[0];

    ri = (data[2] & 0x1F) * CDG_TILE_HEIGHT + cc->vscroll;
    ci = (data[3] & 0x3F) * CDG_TILE_WIDTH  + cc->hscroll;

    if (ri > (CDG_FULL_HEIGHT - CDG_TILE_HEIGHT))
        return AVERROR(EINVAL);
    if (ci > (CDG_FULL_WIDTH - CDG_TILE_WIDTH))
        return AVERROR(EINVAL);

    for (y = 0; y < CDG_TILE_HEIGHT; y++) {
        for (x = 0; x < CDG_TILE_WIDTH; x++) {
            if (!((data[4 + y] >> (5 - x)) & 0x01))
                color = data[0] & 0x0F;
            else
                color = data[1] & 0x0F;

            ai = ci + x + (stride * (ri + y));
            if (b)
                color ^= buf[ai];
            buf[ai] = color;
        }
    }

    return 0;
}

#define UP    2
#define DOWN  1
#define LEFT  2
#define RIGHT 1

static void cdg_copy_rect_buf(int out_tl_x, int out_tl_y, uint8_t *out,
                              int in_tl_x, int in_tl_y, uint8_t *in,
                              int w, int h, int stride)
{
    int y;

    in  += in_tl_x  + in_tl_y  * stride;
    out += out_tl_x + out_tl_y * stride;
    for (y = 0; y < h; y++)
        memcpy(out + y * stride, in + y * stride, w);
}

static void cdg_fill_rect_preset(int tl_x, int tl_y, uint8_t *out,
                                 int color, int w, int h, int stride)
{
    int y;

    for (y = tl_y; y < tl_y + h; y++)
        memset(out + tl_x + y * stride, color, w);
}

static void cdg_fill_wrapper(int out_tl_x, int out_tl_y, uint8_t *out,
                             int in_tl_x, int in_tl_y, uint8_t *in,
                             int color, int w, int h, int stride, int roll)
{
    if (roll) {
        cdg_copy_rect_buf(out_tl_x, out_tl_y, out, in_tl_x, in_tl_y,
                          in, w, h, stride);
    } else {
        cdg_fill_rect_preset(out_tl_x, out_tl_y, out, color, w, h, stride);
    }
}

static void cdg_scroll(CDGraphicsContext *cc, uint8_t *data,
                       AVFrame *new_frame, int roll_over)
{
    int color;
    int hscmd, h_off, hinc, vscmd, v_off, vinc;
    int y;
    int stride   = cc->frame->linesize[0];
    uint8_t *in  = cc->frame->data[0];
    uint8_t *out = new_frame->data[0];

    color =  data[0] & 0x0F;
    hscmd = (data[1] & 0x30) >> 4;
    vscmd = (data[2] & 0x30) >> 4;

    h_off =  FFMIN(data[1] & 0x07, CDG_BORDER_WIDTH  - 1);
    v_off =  FFMIN(data[2] & 0x0F, CDG_BORDER_HEIGHT - 1);

    /// find the difference and save the offset for cdg_tile_block usage
    hinc = h_off - cc->hscroll;
    vinc = v_off - cc->vscroll;
    cc->hscroll = h_off;
    cc->vscroll = v_off;

    if (vscmd == UP)
        vinc -= 12;
    if (vscmd == DOWN)
        vinc += 12;
    if (hscmd == LEFT)
        hinc -= 6;
    if (hscmd == RIGHT)
        hinc += 6;

    if (!hinc && !vinc)
        return;

    memcpy(new_frame->data[1], cc->frame->data[1], CDG_PALETTE_SIZE * 4);

    for (y = FFMAX(0, vinc); y < FFMIN(CDG_FULL_HEIGHT + vinc, CDG_FULL_HEIGHT); y++)
        memcpy(out + FFMAX(0, hinc) + stride * y,
               in + FFMAX(0, hinc) - hinc + (y - vinc) * stride,
               FFMIN(stride + hinc, stride));

    if (vinc > 0)
        cdg_fill_wrapper(0, 0, out,
                         0, CDG_FULL_HEIGHT - vinc, in, color,
                         stride, vinc, stride, roll_over);
    else if (vinc < 0)
        cdg_fill_wrapper(0, CDG_FULL_HEIGHT + vinc, out,
                         0, 0, in, color,
                         stride, -1 * vinc, stride, roll_over);

    if (hinc > 0)
        cdg_fill_wrapper(0, 0, out,
                         CDG_FULL_WIDTH - hinc, 0, in, color,
                         hinc, CDG_FULL_HEIGHT, stride, roll_over);
    else if (hinc < 0)
        cdg_fill_wrapper(CDG_FULL_WIDTH + hinc, 0, out,
                         0, 0, in, color,
                         -1 * hinc, CDG_FULL_HEIGHT, stride, roll_over);

}

static int cdg_decode_frame(AVCodecContext *avctx,
                            void *data, int *got_frame, AVPacket *avpkt)
{
    GetByteContext gb;
    int buf_size       = avpkt->size;
    int ret;
    uint8_t command, inst;
    uint8_t cdg_data[CDG_DATA_SIZE] = {0};
    AVFrame *frame = data;
    CDGraphicsContext *cc = avctx->priv_data;

    if (buf_size < CDG_MINIMUM_PKT_SIZE) {
        av_log(avctx, AV_LOG_ERROR, "buffer too small for decoder\n");
        return AVERROR(EINVAL);
    }
    if (buf_size > CDG_HEADER_SIZE + CDG_DATA_SIZE) {
        av_log(avctx, AV_LOG_ERROR, "buffer too big for decoder\n");
        return AVERROR(EINVAL);
    }

    bytestream2_init(&gb, avpkt->data, avpkt->size);

    if ((ret = ff_reget_buffer(avctx, cc->frame, 0)) < 0)
        return ret;
    if (!cc->cleared) {
        memset(cc->frame->data[0], 0, cc->frame->linesize[0] * avctx->height);
        memset(cc->frame->data[1], 0, AVPALETTE_SIZE);
        cc->cleared = 1;
    }

    command = bytestream2_get_byte(&gb);
    inst    = bytestream2_get_byte(&gb);
    inst    &= CDG_MASK;
    bytestream2_skip(&gb, 2);
    bytestream2_get_buffer(&gb, cdg_data, sizeof(cdg_data));

    if ((command & CDG_MASK) == CDG_COMMAND) {
        switch (inst) {
        case CDG_INST_MEMORY_PRESET:
            if (!(cdg_data[1] & 0x0F))
                memset(cc->frame->data[0], cdg_data[0] & 0x0F,
                       cc->frame->linesize[0] * CDG_FULL_HEIGHT);
            break;
        case CDG_INST_LOAD_PAL_LO:
        case CDG_INST_LOAD_PAL_HIGH:
            if (buf_size - CDG_HEADER_SIZE < CDG_DATA_SIZE) {
                av_log(avctx, AV_LOG_ERROR, "buffer too small for loading palette\n");
                return AVERROR(EINVAL);
            }

            cdg_load_palette(cc, cdg_data, inst == CDG_INST_LOAD_PAL_LO);
            break;
        case CDG_INST_BORDER_PRESET:
            cdg_border_preset(cc, cdg_data);
            break;
        case CDG_INST_TILE_BLOCK_XOR:
        case CDG_INST_TILE_BLOCK:
            if (buf_size - CDG_HEADER_SIZE < CDG_DATA_SIZE) {
                av_log(avctx, AV_LOG_ERROR, "buffer too small for drawing tile\n");
                return AVERROR(EINVAL);
            }

            ret = cdg_tile_block(cc, cdg_data, inst == CDG_INST_TILE_BLOCK_XOR);
            if (ret) {
                av_log(avctx, AV_LOG_ERROR, "tile is out of range\n");
                return ret;
            }
            break;
        case CDG_INST_SCROLL_PRESET:
        case CDG_INST_SCROLL_COPY:
            if (buf_size - CDG_HEADER_SIZE < CDG_MINIMUM_SCROLL_SIZE) {
                av_log(avctx, AV_LOG_ERROR, "buffer too small for scrolling\n");
                return AVERROR(EINVAL);
            }

            if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
                return ret;

            cdg_scroll(cc, cdg_data, frame, inst == CDG_INST_SCROLL_COPY);
            av_frame_unref(cc->frame);
            ret = av_frame_ref(cc->frame, frame);
            if (ret < 0)
                return ret;
            break;
        case CDG_INST_TRANSPARENT_COL:
            cc->transparency = cdg_data[0] & 0xF;
            break;
        default:
            break;
        }

        if (!frame->data[0]) {
            ret = av_frame_ref(frame, cc->frame);
            if (ret < 0)
                return ret;
        }
        *got_frame = 1;
    } else {
        *got_frame = 0;
    }

    return avpkt->size;
}

static av_cold int cdg_decode_end(AVCodecContext *avctx)
{
    CDGraphicsContext *cc = avctx->priv_data;

    av_frame_free(&cc->frame);

    return 0;
}

AVCodec ff_cdgraphics_decoder = {
    .name           = "cdgraphics",
    .long_name      = NULL_IF_CONFIG_SMALL("CD Graphics video"),
    .type           = AVMEDIA_TYPE_VIDEO,
    .id             = AV_CODEC_ID_CDGRAPHICS,
    .priv_data_size = sizeof(CDGraphicsContext),
    .init           = cdg_decode_init,
    .close          = cdg_decode_end,
    .decode         = cdg_decode_frame,
    .capabilities   = AV_CODEC_CAP_DR1,
};


Generated by: GCOVR (Version 4.1)

Line	Branch	Exec	Source
1			/*
2			* CD Graphics Video Decoder
3			* Copyright (c) 2009 Michael Tison
4			*
5			* This file is part of FFmpeg.
6			*
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.
11			*
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.
16			*
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
20			*/
21
22			#include "avcodec.h"
23			#include "bytestream.h"
24			#include "internal.h"
25
26			/**
27			* @file
28			* @brief CD Graphics Video Decoder
29			* @author Michael Tison
30			* @see http://wiki.multimedia.cx/index.php?title=CD_Graphics
31			* @see http://www.ccs.neu.edu/home/bchafy/cdb/info/cdg
32			*/
33
34			/// default screen sizes
35			#define CDG_FULL_WIDTH 300
36			#define CDG_FULL_HEIGHT 216
37			#define CDG_DISPLAY_WIDTH 294
38			#define CDG_DISPLAY_HEIGHT 204
39			#define CDG_BORDER_WIDTH 6
40			#define CDG_BORDER_HEIGHT 12
41
42			/// masks
43			#define CDG_COMMAND 0x09
44			#define CDG_MASK 0x3F
45
46			/// instruction codes
47			#define CDG_INST_MEMORY_PRESET 1
48			#define CDG_INST_BORDER_PRESET 2
49			#define CDG_INST_TILE_BLOCK 6
50			#define CDG_INST_SCROLL_PRESET 20
51			#define CDG_INST_SCROLL_COPY 24
52			#define CDG_INST_TRANSPARENT_COL 28
53			#define CDG_INST_LOAD_PAL_LO 30
54			#define CDG_INST_LOAD_PAL_HIGH 31
55			#define CDG_INST_TILE_BLOCK_XOR 38
56
57			/// data sizes
58			#define CDG_PACKET_SIZE 24
59			#define CDG_DATA_SIZE 16
60			#define CDG_TILE_HEIGHT 12
61			#define CDG_TILE_WIDTH 6
62			#define CDG_MINIMUM_PKT_SIZE 6
63			#define CDG_MINIMUM_SCROLL_SIZE 3
64			#define CDG_HEADER_SIZE 8
65			#define CDG_PALETTE_SIZE 16
66
67			typedef struct CDGraphicsContext {
68			AVFrame *frame;
69			int hscroll;
70			int vscroll;
71			int transparency;
72			int cleared;
73			} CDGraphicsContext;
74
75		2	static av_cold int cdg_decode_init(AVCodecContext *avctx)
76			{
77		2	CDGraphicsContext *cc = avctx->priv_data;
78
79		2	cc->frame = av_frame_alloc();
80	✗✓	2	if (!cc->frame)
81			return AVERROR(ENOMEM);
82		2	cc->transparency = -1;
83
84		2	avctx->pix_fmt = AV_PIX_FMT_PAL8;
85		2	return ff_set_dimensions(avctx, CDG_FULL_WIDTH, CDG_FULL_HEIGHT);
86			}
87
88		6	static void cdg_border_preset(CDGraphicsContext cc, uint8_t data)
89			{
90			int y;
91		6	int lsize = cc->frame->linesize[0];
92		6	uint8_t *buf = cc->frame->data[0];
93		6	int color = data[0] & 0x0F;
94
95	✓✗	6	if (!(data[1] & 0x0F)) {
96			/// fill the top and bottom borders
97		6	memset(buf, color, CDG_BORDER_HEIGHT * lsize);
98		6	memset(buf + (CDG_FULL_HEIGHT - CDG_BORDER_HEIGHT) * lsize,
99		6	color, CDG_BORDER_HEIGHT * lsize);
100
101			/// fill the side borders
102	✓✓	1158	for (y = CDG_BORDER_HEIGHT; y < CDG_FULL_HEIGHT - CDG_BORDER_HEIGHT; y++) {
103		1152	memset(buf + y * lsize, color, CDG_BORDER_WIDTH);
104		1152	memset(buf + CDG_FULL_WIDTH - CDG_BORDER_WIDTH + y * lsize,
105			color, CDG_BORDER_WIDTH);
106			}
107			}
108		6	}
109
110		10	static void cdg_load_palette(CDGraphicsContext cc, uint8_t data, int low)
111			{
112			uint8_t r, g, b;
113			uint16_t color;
114			int i;
115	✓✓	10	int array_offset = low ? 0 : 8;
116		10	uint32_t palette = (uint32_t ) cc->frame->data[1];
117
118	✓✓	90	for (i = 0; i < 8; i++) {
119		80	color = (data[2 * i] << 6) + (data[2 * i + 1] & 0x3F);
120		80	r = ((color >> 8) & 0x000F) * 17;
121		80	g = ((color >> 4) & 0x000F) * 17;
122		80	b = ((color ) & 0x000F) * 17;
123		80	palette[i + array_offset] = 0xFFU << 24 \| r << 16 \| g << 8 \| b;
124	✓✓	80	if (cc->transparency >= 0)
125		16	palette[cc->transparency] &= 0xFFFFFF;
126			}
127		10	cc->frame->palette_has_changed = 1;
128		10	}
129
130		180	static int cdg_tile_block(CDGraphicsContext cc, uint8_t data, int b)
131			{
132			unsigned ci, ri;
133			int color;
134			int x, y;
135			int ai;
136		180	int stride = cc->frame->linesize[0];
137		180	uint8_t *buf = cc->frame->data[0];
138
139		180	ri = (data[2] & 0x1F) * CDG_TILE_HEIGHT + cc->vscroll;
140		180	ci = (data[3] & 0x3F) * CDG_TILE_WIDTH + cc->hscroll;
141
142	✗✓	180	if (ri > (CDG_FULL_HEIGHT - CDG_TILE_HEIGHT))
143			return AVERROR(EINVAL);
144	✗✓	180	if (ci > (CDG_FULL_WIDTH - CDG_TILE_WIDTH))
145			return AVERROR(EINVAL);
146
147	✓✓	2340	for (y = 0; y < CDG_TILE_HEIGHT; y++) {
148	✓✓	15120	for (x = 0; x < CDG_TILE_WIDTH; x++) {
149	✓✓	12960	if (!((data[4 + y] >> (5 - x)) & 0x01))
150		10153	color = data[0] & 0x0F;
151			else
152		2807	color = data[1] & 0x0F;
153
154		12960	ai = ci + x + (stride * (ri + y));
155	✓✗	12960	if (b)
156		12960	color ^= buf[ai];
157		12960	buf[ai] = color;
158			}
159			}
160
161		180	return 0;
162			}
163
164			#define UP 2
165			#define DOWN 1
166			#define LEFT 2
167			#define RIGHT 1
168
169			static void cdg_copy_rect_buf(int out_tl_x, int out_tl_y, uint8_t *out,
170			int in_tl_x, int in_tl_y, uint8_t *in,
171			int w, int h, int stride)
172			{
173			int y;
174
175			in += in_tl_x + in_tl_y * stride;
176			out += out_tl_x + out_tl_y * stride;
177			for (y = 0; y < h; y++)
178			memcpy(out + y * stride, in + y * stride, w);
179			}
180
181			static void cdg_fill_rect_preset(int tl_x, int tl_y, uint8_t *out,
182			int color, int w, int h, int stride)
183			{
184			int y;
185
186			for (y = tl_y; y < tl_y + h; y++)
187			memset(out + tl_x + y * stride, color, w);
188			}
189
190			static void cdg_fill_wrapper(int out_tl_x, int out_tl_y, uint8_t *out,
191			int in_tl_x, int in_tl_y, uint8_t *in,
192			int color, int w, int h, int stride, int roll)
193			{
194			if (roll) {
195			cdg_copy_rect_buf(out_tl_x, out_tl_y, out, in_tl_x, in_tl_y,
196			in, w, h, stride);
197			} else {
198			cdg_fill_rect_preset(out_tl_x, out_tl_y, out, color, w, h, stride);
199			}
200			}
201
202			static void cdg_scroll(CDGraphicsContext cc, uint8_t data,
203			AVFrame *new_frame, int roll_over)
204			{
205			int color;
206			int hscmd, h_off, hinc, vscmd, v_off, vinc;
207			int y;
208			int stride = cc->frame->linesize[0];
209			uint8_t *in = cc->frame->data[0];
210			uint8_t *out = new_frame->data[0];
211
212			color = data[0] & 0x0F;
213			hscmd = (data[1] & 0x30) >> 4;
214			vscmd = (data[2] & 0x30) >> 4;
215
216			h_off = FFMIN(data[1] & 0x07, CDG_BORDER_WIDTH - 1);
217			v_off = FFMIN(data[2] & 0x0F, CDG_BORDER_HEIGHT - 1);
218
219			/// find the difference and save the offset for cdg_tile_block usage
220			hinc = h_off - cc->hscroll;
221			vinc = v_off - cc->vscroll;
222			cc->hscroll = h_off;
223			cc->vscroll = v_off;
224
225			if (vscmd == UP)
226			vinc -= 12;
227			if (vscmd == DOWN)
228			vinc += 12;
229			if (hscmd == LEFT)
230			hinc -= 6;
231			if (hscmd == RIGHT)
232			hinc += 6;
233
234			if (!hinc && !vinc)
235			return;
236
237			memcpy(new_frame->data[1], cc->frame->data[1], CDG_PALETTE_SIZE * 4);
238
239			for (y = FFMAX(0, vinc); y < FFMIN(CDG_FULL_HEIGHT + vinc, CDG_FULL_HEIGHT); y++)
240			memcpy(out + FFMAX(0, hinc) + stride * y,
241			in + FFMAX(0, hinc) - hinc + (y - vinc) * stride,
242			FFMIN(stride + hinc, stride));
243
244			if (vinc > 0)
245			cdg_fill_wrapper(0, 0, out,
246			0, CDG_FULL_HEIGHT - vinc, in, color,
247			stride, vinc, stride, roll_over);
248			else if (vinc < 0)
249			cdg_fill_wrapper(0, CDG_FULL_HEIGHT + vinc, out,
250			0, 0, in, color,
251			stride, -1 * vinc, stride, roll_over);
252
253			if (hinc > 0)
254			cdg_fill_wrapper(0, 0, out,
255			CDG_FULL_WIDTH - hinc, 0, in, color,
256			hinc, CDG_FULL_HEIGHT, stride, roll_over);
257			else if (hinc < 0)
258			cdg_fill_wrapper(CDG_FULL_WIDTH + hinc, 0, out,
259			0, 0, in, color,
260			-1 * hinc, CDG_FULL_HEIGHT, stride, roll_over);
261
262			}
263
264		213	static int cdg_decode_frame(AVCodecContext *avctx,
265			void data, int got_frame, AVPacket *avpkt)
266			{
267			GetByteContext gb;
268		213	int buf_size = avpkt->size;
269			int ret;
270			uint8_t command, inst;
271		213	uint8_t cdg_data[CDG_DATA_SIZE] = {0};
272		213	AVFrame *frame = data;
273		213	CDGraphicsContext *cc = avctx->priv_data;
274
275	✗✓	213	if (buf_size < CDG_MINIMUM_PKT_SIZE) {
276			av_log(avctx, AV_LOG_ERROR, "buffer too small for decoder\n");
277			return AVERROR(EINVAL);
278			}
279	✗✓	213	if (buf_size > CDG_HEADER_SIZE + CDG_DATA_SIZE) {
280			av_log(avctx, AV_LOG_ERROR, "buffer too big for decoder\n");
281			return AVERROR(EINVAL);
282			}
283
284		213	bytestream2_init(&gb, avpkt->data, avpkt->size);
285
286	✗✓	213	if ((ret = ff_reget_buffer(avctx, cc->frame, 0)) < 0)
287			return ret;
288	✓✓	213	if (!cc->cleared) {
289		1	memset(cc->frame->data[0], 0, cc->frame->linesize[0] * avctx->height);
290		1	memset(cc->frame->data[1], 0, AVPALETTE_SIZE);
291		1	cc->cleared = 1;
292			}
293
294		213	command = bytestream2_get_byte(&gb);
295		213	inst = bytestream2_get_byte(&gb);
296		213	inst &= CDG_MASK;
297		213	bytestream2_skip(&gb, 2);
298		213	bytestream2_get_buffer(&gb, cdg_data, sizeof(cdg_data));
299
300	✓✗	213	if ((command & CDG_MASK) == CDG_COMMAND) {
301	✓✓✓✓ ✗✓✗	213	switch (inst) {
302		16	case CDG_INST_MEMORY_PRESET:
303	✓✓	16	if (!(cdg_data[1] & 0x0F))
304		1	memset(cc->frame->data[0], cdg_data[0] & 0x0F,
305		1	cc->frame->linesize[0] * CDG_FULL_HEIGHT);
306		16	break;
307		10	case CDG_INST_LOAD_PAL_LO:
308			case CDG_INST_LOAD_PAL_HIGH:
309	✗✓	10	if (buf_size - CDG_HEADER_SIZE < CDG_DATA_SIZE) {
310			av_log(avctx, AV_LOG_ERROR, "buffer too small for loading palette\n");
311			return AVERROR(EINVAL);
312			}
313
314		10	cdg_load_palette(cc, cdg_data, inst == CDG_INST_LOAD_PAL_LO);
315		10	break;
316		6	case CDG_INST_BORDER_PRESET:
317		6	cdg_border_preset(cc, cdg_data);
318		6	break;
319		180	case CDG_INST_TILE_BLOCK_XOR:
320			case CDG_INST_TILE_BLOCK:
321	✗✓	180	if (buf_size - CDG_HEADER_SIZE < CDG_DATA_SIZE) {
322			av_log(avctx, AV_LOG_ERROR, "buffer too small for drawing tile\n");
323			return AVERROR(EINVAL);
324			}
325
326		180	ret = cdg_tile_block(cc, cdg_data, inst == CDG_INST_TILE_BLOCK_XOR);
327	✗✓	180	if (ret) {
328			av_log(avctx, AV_LOG_ERROR, "tile is out of range\n");
329			return ret;
330			}
331		180	break;
332			case CDG_INST_SCROLL_PRESET:
333			case CDG_INST_SCROLL_COPY:
334			if (buf_size - CDG_HEADER_SIZE < CDG_MINIMUM_SCROLL_SIZE) {
335			av_log(avctx, AV_LOG_ERROR, "buffer too small for scrolling\n");
336			return AVERROR(EINVAL);
337			}
338
339			if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
340			return ret;
341
342			cdg_scroll(cc, cdg_data, frame, inst == CDG_INST_SCROLL_COPY);
343			av_frame_unref(cc->frame);
344			ret = av_frame_ref(cc->frame, frame);
345			if (ret < 0)
346			return ret;
347			break;
348		1	case CDG_INST_TRANSPARENT_COL:
349		1	cc->transparency = cdg_data[0] & 0xF;
350		1	break;
351			default:
352			break;
353			}
354
355	✓✗	213	if (!frame->data[0]) {
356		213	ret = av_frame_ref(frame, cc->frame);
357	✗✓	213	if (ret < 0)
358			return ret;
359			}
360		213	*got_frame = 1;
361			} else {
362			*got_frame = 0;
363			}
364
365		213	return avpkt->size;
366			}
367
368		2	static av_cold int cdg_decode_end(AVCodecContext *avctx)
369			{
370		2	CDGraphicsContext *cc = avctx->priv_data;
371
372		2	av_frame_free(&cc->frame);
373
374		2	return 0;
375			}
376
377			AVCodec ff_cdgraphics_decoder = {
378			.name = "cdgraphics",
379			.long_name = NULL_IF_CONFIG_SMALL("CD Graphics video"),
380			.type = AVMEDIA_TYPE_VIDEO,
381			.id = AV_CODEC_ID_CDGRAPHICS,
382			.priv_data_size = sizeof(CDGraphicsContext),
383			.init = cdg_decode_init,
384			.close = cdg_decode_end,
385			.decode = cdg_decode_frame,
386			.capabilities = AV_CODEC_CAP_DR1,
387			};