FFmpeg coverage

GCC Code Coverage Report

Directory:	../../../ffmpeg/		Exec	Total	Coverage
File:	src/libavcodec/tscc2.c	Lines:	153	192	79.7 %
Date:	2020-08-14 10:39:37	Branches:	81	110	73.6 %


/*
 * TechSmith Screen Codec 2 (aka Dora) decoder
 * Copyright (c) 2012 Konstantin Shishkov
 *
 * 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
 */

/**
 * @file
 * TechSmith Screen Codec 2 decoder
 */

#include <inttypes.h>

#define BITSTREAM_READER_LE
#include "avcodec.h"
#include "bytestream.h"
#include "get_bits.h"
#include "internal.h"
#include "mathops.h"
#include "tscc2data.h"

typedef struct TSCC2Context {
    AVCodecContext *avctx;
    AVFrame       *pic;
    int            mb_width, mb_height;
    uint8_t        *slice_quants;
    int            quant[2];
    int            q[2][3];
    GetBitContext  gb;

    VLC            dc_vlc, nc_vlc[NUM_VLC_SETS], ac_vlc[NUM_VLC_SETS];
    int            block[16];
} TSCC2Context;

static av_cold void free_vlcs(TSCC2Context *c)
{
    int i;

    ff_free_vlc(&c->dc_vlc);
    for (i = 0; i < NUM_VLC_SETS; i++) {
        ff_free_vlc(c->nc_vlc + i);
        ff_free_vlc(c->ac_vlc + i);
    }
}

static av_cold int init_vlcs(TSCC2Context *c)
{
    int i, ret;

    ret = ff_init_vlc_sparse(&c->dc_vlc, 9, DC_VLC_COUNT,
                             tscc2_dc_vlc_bits,  1, 1,
                             tscc2_dc_vlc_codes, 2, 2,
                             tscc2_dc_vlc_syms,  2, 2, INIT_VLC_LE);
    if (ret)
        return ret;

    for (i = 0; i < NUM_VLC_SETS; i++) {
        ret = ff_init_vlc_sparse(c->nc_vlc + i, 9, 16,
                                 tscc2_nc_vlc_bits[i],  1, 1,
                                 tscc2_nc_vlc_codes[i], 2, 2,
                                 tscc2_nc_vlc_syms,     1, 1, INIT_VLC_LE);
        if (ret) {
            free_vlcs(c);
            return ret;
        }
        ret = ff_init_vlc_sparse(c->ac_vlc + i, 9, tscc2_ac_vlc_sizes[i],
                                 tscc2_ac_vlc_bits[i],  1, 1,
                                 tscc2_ac_vlc_codes[i], 2, 2,
                                 tscc2_ac_vlc_syms[i],  2, 2, INIT_VLC_LE);
        if (ret) {
            free_vlcs(c);
            return ret;
        }
    }

    return 0;
}

#define DEQUANT(val, q) (((q) * (val) + 0x80) >> 8)
#define DCT1D(d0, d1, d2, d3, s0, s1, s2, s3, OP) \
    OP(d0, 5 * ((s0) + (s1) + (s2)) + 2 * (s3));  \
    OP(d1, 5 * ((s0) - (s2) - (s3)) + 2 * (s1));  \
    OP(d2, 5 * ((s0) - (s2) + (s3)) - 2 * (s1));  \
    OP(d3, 5 * ((s0) - (s1) + (s2)) - 2 * (s3));  \

#define COL_OP(a, b)  a = (b)
#define ROW_OP(a, b)  a = ((b) + 0x20) >> 6

static void tscc2_idct4_put(int *in, int q[3], uint8_t *dst, int stride)
{
    int i;
    int tblk[4 * 4];
    int t0, t1, t2, t3;

    for (i = 0; i < 4; i++) {
        t0 = DEQUANT(q[0 + (i & 1)], in[0 * 4 + i]);
        t1 = DEQUANT(q[1 + (i & 1)], in[1 * 4 + i]);
        t2 = DEQUANT(q[0 + (i & 1)], in[2 * 4 + i]);
        t3 = DEQUANT(q[1 + (i & 1)], in[3 * 4 + i]);
        DCT1D(tblk[0 * 4 + i], tblk[1 * 4 + i],
              tblk[2 * 4 + i], tblk[3 * 4 + i],
              t0, t1, t2, t3, COL_OP);
    }
    for (i = 0; i < 4; i++) {
        DCT1D(dst[0], dst[1], dst[2], dst[3],
              tblk[i * 4 + 0], tblk[i * 4 + 1],
              tblk[i * 4 + 2], tblk[i * 4 + 3], ROW_OP);
        dst += stride;
    }
}

static int tscc2_decode_mb(TSCC2Context *c, int *q, int vlc_set,
                           uint8_t *dst, int stride, int plane)
{
    GetBitContext *gb = &c->gb;
    int prev_dc, dc, nc, ac, bpos, val;
    int i, j, k, l;

    if (get_bits1(gb)) {
        if (get_bits1(gb)) {
            val = get_bits(gb, 8);
            for (i = 0; i < 8; i++, dst += stride)
                memset(dst, val, 16);
        } else {
            if (get_bits_left(gb) < 16 * 8 * 8)
                return AVERROR_INVALIDDATA;
            for (i = 0; i < 8; i++) {
                for (j = 0; j < 16; j++)
                    dst[j] = get_bits(gb, 8);
                dst += stride;
            }
        }
        return 0;
    }

    prev_dc = 0;
    for (j = 0; j < 2; j++) {
        for (k = 0; k < 4; k++) {
            if (!(j | k)) {
                dc = get_bits(gb, 8);
            } else {
                dc = get_vlc2(gb, c->dc_vlc.table, 9, 2);
                if (dc == -1)
                    return AVERROR_INVALIDDATA;
                if (dc == 0x100)
                    dc = get_bits(gb, 8);
            }
            dc          = (dc + prev_dc) & 0xFF;
            prev_dc     = dc;
            c->block[0] = dc;

            nc = get_vlc2(gb, c->nc_vlc[vlc_set].table, 9, 1);
            if (nc == -1)
                return AVERROR_INVALIDDATA;

            bpos = 1;
            memset(c->block + 1, 0, 15 * sizeof(*c->block));
            for (l = 0; l < nc; l++) {
                ac = get_vlc2(gb, c->ac_vlc[vlc_set].table, 9, 2);
                if (ac == -1)
                    return AVERROR_INVALIDDATA;
                if (ac == 0x1000)
                    ac = get_bits(gb, 12);
                bpos += ac & 0xF;
                if (bpos >= 16)
                    return AVERROR_INVALIDDATA;
                val = sign_extend(ac >> 4, 8);
                c->block[ff_zigzag_scan[bpos++]] = val;
            }
            tscc2_idct4_put(c->block, q, dst + k * 4, stride);
        }
        dst += 4 * stride;
    }
    return 0;
}

static int tscc2_decode_slice(TSCC2Context *c, int mb_y,
                              const uint8_t *buf, int buf_size)
{
    int i, mb_x, q, ret;
    int off;

    if ((ret = init_get_bits8(&c->gb, buf, buf_size)) < 0)
        return ret;

    for (mb_x = 0; mb_x < c->mb_width; mb_x++) {
        q = c->slice_quants[mb_x + c->mb_width * mb_y];

        if (q == 0 || q == 3) // skip block
            continue;
        for (i = 0; i < 3; i++) {
            off = mb_x * 16 + mb_y * 8 * c->pic->linesize[i];
            ret = tscc2_decode_mb(c, c->q[q - 1], c->quant[q - 1] - 2,
                                  c->pic->data[i] + off, c->pic->linesize[i], i);
            if (ret)
                return ret;
        }
    }

    return 0;
}

static int tscc2_decode_frame(AVCodecContext *avctx, void *data,
                              int *got_frame, AVPacket *avpkt)
{
    const uint8_t *buf = avpkt->data;
    int buf_size = avpkt->size;
    TSCC2Context *c = avctx->priv_data;
    GetByteContext gb;
    uint32_t frame_type, size;
    int i, val, len, pos = 0;
    int num_mb = c->mb_width * c->mb_height;
    int ret;

    bytestream2_init(&gb, buf, buf_size);
    frame_type = bytestream2_get_byte(&gb);
    if (frame_type > 1) {
        av_log(avctx, AV_LOG_ERROR, "Incorrect frame type %"PRIu32"\n",
               frame_type);
        return AVERROR_INVALIDDATA;
    }

    if (frame_type == 0) {
        // Skip duplicate frames
        return buf_size;
    }

    if ((ret = ff_reget_buffer(avctx, c->pic, 0)) < 0) {
        return ret;
    }

    if (bytestream2_get_bytes_left(&gb) < 4) {
        av_log(avctx, AV_LOG_ERROR, "Frame is too short\n");
        return AVERROR_INVALIDDATA;
    }

    c->quant[0] = bytestream2_get_byte(&gb);
    c->quant[1] = bytestream2_get_byte(&gb);
    if (c->quant[0] < 2 || c->quant[0] > NUM_VLC_SETS + 1 ||
        c->quant[1] < 2 || c->quant[1] > NUM_VLC_SETS + 1) {
        av_log(avctx, AV_LOG_ERROR, "Invalid quantisers %d / %d\n",
               c->quant[0], c->quant[1]);
        return AVERROR_INVALIDDATA;
    }

    for (i = 0; i < 3; i++) {
        c->q[0][i] = tscc2_quants[c->quant[0] - 2][i];
        c->q[1][i] = tscc2_quants[c->quant[1] - 2][i];
    }

    bytestream2_skip(&gb, 1);

    size = bytestream2_get_le32(&gb);
    if (size > bytestream2_get_bytes_left(&gb)) {
        av_log(avctx, AV_LOG_ERROR, "Slice properties chunk is too large\n");
        return AVERROR_INVALIDDATA;
    }

    for (i = 0; i < size; i++) {
        val   = bytestream2_get_byte(&gb);
        len   = val & 0x3F;
        val >>= 6;
        if (pos + len > num_mb) {
            av_log(avctx, AV_LOG_ERROR, "Too many slice properties\n");
            return AVERROR_INVALIDDATA;
        }
        memset(c->slice_quants + pos, val, len);
        pos += len;
    }
    if (pos < num_mb) {
        av_log(avctx, AV_LOG_ERROR, "Too few slice properties (%d / %d)\n",
               pos, num_mb);
        return AVERROR_INVALIDDATA;
    }

    for (i = 0; i < c->mb_height; i++) {
        size = bytestream2_peek_byte(&gb);
        if (size & 1) {
            size = bytestream2_get_byte(&gb) - 1;
        } else {
            size = bytestream2_get_le32(&gb) >> 1;
        }
        if (!size) {
            int skip_row = 1, j, off = i * c->mb_width;
            for (j = 0; j < c->mb_width; j++) {
                if (c->slice_quants[off + j] == 1 ||
                    c->slice_quants[off + j] == 2) {
                    skip_row = 0;
                    break;
                }
            }
            if (!skip_row) {
                av_log(avctx, AV_LOG_ERROR, "Non-skip row with zero size\n");
                return AVERROR_INVALIDDATA;
            }
        }
        if (bytestream2_get_bytes_left(&gb) < size) {
            av_log(avctx, AV_LOG_ERROR, "Invalid slice size (%"PRIu32"/%u)\n",
                   size, bytestream2_get_bytes_left(&gb));
            return AVERROR_INVALIDDATA;
        }
        ret = tscc2_decode_slice(c, i, buf + bytestream2_tell(&gb), size);
        if (ret) {
            av_log(avctx, AV_LOG_ERROR, "Error decoding slice %d\n", i);
            return ret;
        }
        bytestream2_skip(&gb, size);
    }

    *got_frame      = 1;
    if ((ret = av_frame_ref(data, c->pic)) < 0)
        return ret;

    /* always report that the buffer was completely consumed */
    return buf_size;
}

static av_cold int tscc2_decode_end(AVCodecContext *avctx)
{
    TSCC2Context * const c = avctx->priv_data;

    av_frame_free(&c->pic);
    av_freep(&c->slice_quants);
    free_vlcs(c);

    return 0;
}

static av_cold int tscc2_decode_init(AVCodecContext *avctx)
{
    TSCC2Context * const c = avctx->priv_data;
    int ret;

    c->avctx = avctx;

    avctx->pix_fmt = AV_PIX_FMT_YUV444P;

    if ((ret = init_vlcs(c)) < 0) {
        av_log(avctx, AV_LOG_ERROR, "Cannot initialise VLCs\n");
        return ret;
    }

    c->mb_width     = FFALIGN(avctx->width,  16) >> 4;
    c->mb_height    = FFALIGN(avctx->height,  8) >> 3;
    c->slice_quants = av_malloc(c->mb_width * c->mb_height);
    if (!c->slice_quants) {
        av_log(avctx, AV_LOG_ERROR, "Cannot allocate slice information\n");
        free_vlcs(c);
        return AVERROR(ENOMEM);
    }

    c->pic = av_frame_alloc();
    if (!c->pic) {
        tscc2_decode_end(avctx);
        return AVERROR(ENOMEM);
    }

    return 0;
}

AVCodec ff_tscc2_decoder = {
    .name           = "tscc2",
    .long_name      = NULL_IF_CONFIG_SMALL("TechSmith Screen Codec 2"),
    .type           = AVMEDIA_TYPE_VIDEO,
    .id             = AV_CODEC_ID_TSCC2,
    .priv_data_size = sizeof(TSCC2Context),
    .init           = tscc2_decode_init,
    .close          = tscc2_decode_end,
    .decode         = tscc2_decode_frame,
    .capabilities   = AV_CODEC_CAP_DR1,
};


Generated by: GCOVR (Version 4.2)

Line	Branch	Exec	Source
1			/*
2			* TechSmith Screen Codec 2 (aka Dora) decoder
3			* Copyright (c) 2012 Konstantin Shishkov
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			/**
23			* @file
24			* TechSmith Screen Codec 2 decoder
25			*/
26
27			#include <inttypes.h>
28
29			#define BITSTREAM_READER_LE
30			#include "avcodec.h"
31			#include "bytestream.h"
32			#include "get_bits.h"
33			#include "internal.h"
34			#include "mathops.h"
35			#include "tscc2data.h"
36
37			typedef struct TSCC2Context {
38			AVCodecContext *avctx;
39			AVFrame *pic;
40			int mb_width, mb_height;
41			uint8_t *slice_quants;
42			int quant[2];
43			int q[2][3];
44			GetBitContext gb;
45
46			VLC dc_vlc, nc_vlc[NUM_VLC_SETS], ac_vlc[NUM_VLC_SETS];
47			int block[16];
48			} TSCC2Context;
49
50		4	static av_cold void free_vlcs(TSCC2Context *c)
51			{
52			int i;
53
54		4	ff_free_vlc(&c->dc_vlc);
55	✓✓	56	for (i = 0; i < NUM_VLC_SETS; i++) {
56		52	ff_free_vlc(c->nc_vlc + i);
57		52	ff_free_vlc(c->ac_vlc + i);
58			}
59		4	}
60
61		4	static av_cold int init_vlcs(TSCC2Context *c)
62			{
63			int i, ret;
64
65		4	ret = ff_init_vlc_sparse(&c->dc_vlc, 9, DC_VLC_COUNT,
66			tscc2_dc_vlc_bits, 1, 1,
67			tscc2_dc_vlc_codes, 2, 2,
68			tscc2_dc_vlc_syms, 2, 2, INIT_VLC_LE);
69	✗✓	4	if (ret)
70			return ret;
71
72	✓✓	56	for (i = 0; i < NUM_VLC_SETS; i++) {
73		52	ret = ff_init_vlc_sparse(c->nc_vlc + i, 9, 16,
74		52	tscc2_nc_vlc_bits[i], 1, 1,
75		52	tscc2_nc_vlc_codes[i], 2, 2,
76			tscc2_nc_vlc_syms, 1, 1, INIT_VLC_LE);
77	✗✓	52	if (ret) {
78			free_vlcs(c);
79			return ret;
80			}
81		52	ret = ff_init_vlc_sparse(c->ac_vlc + i, 9, tscc2_ac_vlc_sizes[i],
82		52	tscc2_ac_vlc_bits[i], 1, 1,
83		52	tscc2_ac_vlc_codes[i], 2, 2,
84		52	tscc2_ac_vlc_syms[i], 2, 2, INIT_VLC_LE);
85	✗✓	52	if (ret) {
86			free_vlcs(c);
87			return ret;
88			}
89			}
90
91		4	return 0;
92			}
93
94			#define DEQUANT(val, q) (((q) * (val) + 0x80) >> 8)
95			#define DCT1D(d0, d1, d2, d3, s0, s1, s2, s3, OP) \
96			OP(d0, 5 * ((s0) + (s1) + (s2)) + 2 * (s3)); \
97			OP(d1, 5 * ((s0) - (s2) - (s3)) + 2 * (s1)); \
98			OP(d2, 5 * ((s0) - (s2) + (s3)) - 2 * (s1)); \
99			OP(d3, 5 * ((s0) - (s1) + (s2)) - 2 * (s3)); \
100
101			#define COL_OP(a, b) a = (b)
102			#define ROW_OP(a, b) a = ((b) + 0x20) >> 6
103
104		441488	static void tscc2_idct4_put(int in, int q[3], uint8_t dst, int stride)
105			{
106			int i;
107			int tblk[4 * 4];
108			int t0, t1, t2, t3;
109
110	✓✓	2207440	for (i = 0; i < 4; i++) {
111		1765952	t0 = DEQUANT(q[0 + (i & 1)], in[0 * 4 + i]);
112		1765952	t1 = DEQUANT(q[1 + (i & 1)], in[1 * 4 + i]);
113		1765952	t2 = DEQUANT(q[0 + (i & 1)], in[2 * 4 + i]);
114		1765952	t3 = DEQUANT(q[1 + (i & 1)], in[3 * 4 + i]);
115		1765952	DCT1D(tblk[0 * 4 + i], tblk[1 * 4 + i],
116			tblk[2 * 4 + i], tblk[3 * 4 + i],
117			t0, t1, t2, t3, COL_OP);
118			}
119	✓✓	2207440	for (i = 0; i < 4; i++) {
120		1765952	DCT1D(dst[0], dst[1], dst[2], dst[3],
121			tblk[i * 4 + 0], tblk[i * 4 + 1],
122			tblk[i * 4 + 2], tblk[i * 4 + 3], ROW_OP);
123		1765952	dst += stride;
124			}
125		441488	}
126
127		66141	static int tscc2_decode_mb(TSCC2Context c, int q, int vlc_set,
128			uint8_t *dst, int stride, int plane)
129			{
130		66141	GetBitContext *gb = &c->gb;
131			int prev_dc, dc, nc, ac, bpos, val;
132			int i, j, k, l;
133
134	✓✓	66141	if (get_bits1(gb)) {
135	✓✓	10955	if (get_bits1(gb)) {
136		10954	val = get_bits(gb, 8);
137	✓✓	98586	for (i = 0; i < 8; i++, dst += stride)
138		87632	memset(dst, val, 16);
139			} else {
140	✗✓	1	if (get_bits_left(gb) < 16 * 8 * 8)
141			return AVERROR_INVALIDDATA;
142	✓✓	9	for (i = 0; i < 8; i++) {
143	✓✓	136	for (j = 0; j < 16; j++)
144		128	dst[j] = get_bits(gb, 8);
145		8	dst += stride;
146			}
147			}
148		10955	return 0;
149			}
150
151		55186	prev_dc = 0;
152	✓✓	165558	for (j = 0; j < 2; j++) {
153	✓✓	551860	for (k = 0; k < 4; k++) {
154	✓✓	441488	if (!(j \| k)) {
155		55186	dc = get_bits(gb, 8);
156			} else {
157		386302	dc = get_vlc2(gb, c->dc_vlc.table, 9, 2);
158	✗✓	386302	if (dc == -1)
159			return AVERROR_INVALIDDATA;
160	✓✓	386302	if (dc == 0x100)
161		22622	dc = get_bits(gb, 8);
162			}
163		441488	dc = (dc + prev_dc) & 0xFF;
164		441488	prev_dc = dc;
165		441488	c->block[0] = dc;
166
167		441488	nc = get_vlc2(gb, c->nc_vlc[vlc_set].table, 9, 1);
168	✗✓	441488	if (nc == -1)
169			return AVERROR_INVALIDDATA;
170
171		441488	bpos = 1;
172		441488	memset(c->block + 1, 0, 15 * sizeof(*c->block));
173	✓✓	2082935	for (l = 0; l < nc; l++) {
174		1641447	ac = get_vlc2(gb, c->ac_vlc[vlc_set].table, 9, 2);
175	✗✓	1641447	if (ac == -1)
176			return AVERROR_INVALIDDATA;
177	✓✓	1641447	if (ac == 0x1000)
178		48321	ac = get_bits(gb, 12);
179		1641447	bpos += ac & 0xF;
180	✗✓	1641447	if (bpos >= 16)
181			return AVERROR_INVALIDDATA;
182		1641447	val = sign_extend(ac >> 4, 8);
183		1641447	c->block[ff_zigzag_scan[bpos++]] = val;
184			}
185		441488	tscc2_idct4_put(c->block, q, dst + k * 4, stride);
186			}
187		110372	dst += 4 * stride;
188			}
189		55186	return 0;
190			}
191
192		1084	static int tscc2_decode_slice(TSCC2Context *c, int mb_y,
193			const uint8_t *buf, int buf_size)
194			{
195			int i, mb_x, q, ret;
196			int off;
197
198	✗✓	1084	if ((ret = init_get_bits8(&c->gb, buf, buf_size)) < 0)
199			return ret;
200
201	✓✓	34860	for (mb_x = 0; mb_x < c->mb_width; mb_x++) {
202		33776	q = c->slice_quants[mb_x + c->mb_width * mb_y];
203
204	✓✓✗✓	33776	if (q == 0 \|\| q == 3) // skip block
205		11729	continue;
206	✓✓	88188	for (i = 0; i < 3; i++) {
207		66141	off = mb_x * 16 + mb_y * 8 * c->pic->linesize[i];
208		66141	ret = tscc2_decode_mb(c, c->q[q - 1], c->quant[q - 1] - 2,
209		66141	c->pic->data[i] + off, c->pic->linesize[i], i);
210	✗✓	66141	if (ret)
211			return ret;
212			}
213			}
214
215		1084	return 0;
216			}
217
218		48	static int tscc2_decode_frame(AVCodecContext avctx, void data,
219			int got_frame, AVPacket avpkt)
220			{
221		48	const uint8_t *buf = avpkt->data;
222		48	int buf_size = avpkt->size;
223		48	TSCC2Context *c = avctx->priv_data;
224			GetByteContext gb;
225			uint32_t frame_type, size;
226		48	int i, val, len, pos = 0;
227		48	int num_mb = c->mb_width * c->mb_height;
228			int ret;
229
230		48	bytestream2_init(&gb, buf, buf_size);
231		48	frame_type = bytestream2_get_byte(&gb);
232	✗✓	48	if (frame_type > 1) {
233			av_log(avctx, AV_LOG_ERROR, "Incorrect frame type %"PRIu32"\n",
234			frame_type);
235			return AVERROR_INVALIDDATA;
236			}
237
238	✓✓	48	if (frame_type == 0) {
239			// Skip duplicate frames
240		17	return buf_size;
241			}
242
243	✗✓	31	if ((ret = ff_reget_buffer(avctx, c->pic, 0)) < 0) {
244			return ret;
245			}
246
247	✗✓	31	if (bytestream2_get_bytes_left(&gb) < 4) {
248			av_log(avctx, AV_LOG_ERROR, "Frame is too short\n");
249			return AVERROR_INVALIDDATA;
250			}
251
252		31	c->quant[0] = bytestream2_get_byte(&gb);
253		31	c->quant[1] = bytestream2_get_byte(&gb);
254	✓✗✓✗	31	if (c->quant[0] < 2 \|\| c->quant[0] > NUM_VLC_SETS + 1 \|\|
255	✓✗✗✓	31	c->quant[1] < 2 \|\| c->quant[1] > NUM_VLC_SETS + 1) {
256			av_log(avctx, AV_LOG_ERROR, "Invalid quantisers %d / %d\n",
257			c->quant[0], c->quant[1]);
258			return AVERROR_INVALIDDATA;
259			}
260
261	✓✓	124	for (i = 0; i < 3; i++) {
262		93	c->q[0][i] = tscc2_quants[c->quant[0] - 2][i];
263		93	c->q[1][i] = tscc2_quants[c->quant[1] - 2][i];
264			}
265
266		31	bytestream2_skip(&gb, 1);
267
268		31	size = bytestream2_get_le32(&gb);
269	✗✓	31	if (size > bytestream2_get_bytes_left(&gb)) {
270			av_log(avctx, AV_LOG_ERROR, "Slice properties chunk is too large\n");
271			return AVERROR_INVALIDDATA;
272			}
273
274	✓✓	3319	for (i = 0; i < size; i++) {
275		3288	val = bytestream2_get_byte(&gb);
276		3288	len = val & 0x3F;
277		3288	val >>= 6;
278	✗✓	3288	if (pos + len > num_mb) {
279			av_log(avctx, AV_LOG_ERROR, "Too many slice properties\n");
280			return AVERROR_INVALIDDATA;
281			}
282		3288	memset(c->slice_quants + pos, val, len);
283		3288	pos += len;
284			}
285	✗✓	31	if (pos < num_mb) {
286			av_log(avctx, AV_LOG_ERROR, "Too few slice properties (%d / %d)\n",
287			pos, num_mb);
288			return AVERROR_INVALIDDATA;
289			}
290
291	✓✓	1115	for (i = 0; i < c->mb_height; i++) {
292		1085	size = bytestream2_peek_byte(&gb);
293	✓✓	1085	if (size & 1) {
294		103	size = bytestream2_get_byte(&gb) - 1;
295			} else {
296		982	size = bytestream2_get_le32(&gb) >> 1;
297			}
298	✓✓	1085	if (!size) {
299		103	int skip_row = 1, j, off = i * c->mb_width;
300	✓✓	5871	for (j = 0; j < c->mb_width; j++) {
301	✓✗	5768	if (c->slice_quants[off + j] == 1 \|\|
302	✗✓	5768	c->slice_quants[off + j] == 2) {
303			skip_row = 0;
304			break;
305			}
306			}
307	✗✓	103	if (!skip_row) {
308			av_log(avctx, AV_LOG_ERROR, "Non-skip row with zero size\n");
309			return AVERROR_INVALIDDATA;
310			}
311			}
312	✓✓	1085	if (bytestream2_get_bytes_left(&gb) < size) {
313		1	av_log(avctx, AV_LOG_ERROR, "Invalid slice size (%"PRIu32"/%u)\n",
314			size, bytestream2_get_bytes_left(&gb));
315		1	return AVERROR_INVALIDDATA;
316			}
317		1084	ret = tscc2_decode_slice(c, i, buf + bytestream2_tell(&gb), size);
318	✗✓	1084	if (ret) {
319			av_log(avctx, AV_LOG_ERROR, "Error decoding slice %d\n", i);
320			return ret;
321			}
322		1084	bytestream2_skip(&gb, size);
323			}
324
325		30	*got_frame = 1;
326	✗✓	30	if ((ret = av_frame_ref(data, c->pic)) < 0)
327			return ret;
328
329			/* always report that the buffer was completely consumed */
330		30	return buf_size;
331			}
332
333		4	static av_cold int tscc2_decode_end(AVCodecContext *avctx)
334			{
335		4	TSCC2Context * const c = avctx->priv_data;
336
337		4	av_frame_free(&c->pic);
338		4	av_freep(&c->slice_quants);
339		4	free_vlcs(c);
340
341		4	return 0;
342			}
343
344		4	static av_cold int tscc2_decode_init(AVCodecContext *avctx)
345			{
346		4	TSCC2Context * const c = avctx->priv_data;
347			int ret;
348
349		4	c->avctx = avctx;
350
351		4	avctx->pix_fmt = AV_PIX_FMT_YUV444P;
352
353	✗✓	4	if ((ret = init_vlcs(c)) < 0) {
354			av_log(avctx, AV_LOG_ERROR, "Cannot initialise VLCs\n");
355			return ret;
356			}
357
358		4	c->mb_width = FFALIGN(avctx->width, 16) >> 4;
359		4	c->mb_height = FFALIGN(avctx->height, 8) >> 3;
360		4	c->slice_quants = av_malloc(c->mb_width * c->mb_height);
361	✗✓	4	if (!c->slice_quants) {
362			av_log(avctx, AV_LOG_ERROR, "Cannot allocate slice information\n");
363			free_vlcs(c);
364			return AVERROR(ENOMEM);
365			}
366
367		4	c->pic = av_frame_alloc();
368	✗✓	4	if (!c->pic) {
369			tscc2_decode_end(avctx);
370			return AVERROR(ENOMEM);
371			}
372
373		4	return 0;
374			}
375
376			AVCodec ff_tscc2_decoder = {
377			.name = "tscc2",
378			.long_name = NULL_IF_CONFIG_SMALL("TechSmith Screen Codec 2"),
379			.type = AVMEDIA_TYPE_VIDEO,
380			.id = AV_CODEC_ID_TSCC2,
381			.priv_data_size = sizeof(TSCC2Context),
382			.init = tscc2_decode_init,
383			.close = tscc2_decode_end,
384			.decode = tscc2_decode_frame,
385			.capabilities = AV_CODEC_CAP_DR1,
386			};