xref: /third_party/ffmpeg/libavcodec/cljrdec.c (revision cabdff1a)
1/*
2 * Cirrus Logic AccuPak (CLJR) decoder
3 * Copyright (c) 2003 Alex Beregszaszi
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 * Cirrus Logic AccuPak decoder.
25 */
26
27#include "avcodec.h"
28#include "codec_internal.h"
29#include "get_bits.h"
30#include "internal.h"
31
32static int decode_frame(AVCodecContext *avctx, AVFrame *p,
33                        int *got_frame, AVPacket *avpkt)
34{
35    const uint8_t *buf = avpkt->data;
36    int buf_size       = avpkt->size;
37    GetBitContext gb;
38    int x, y, ret;
39
40    if (avctx->height <= 0 || avctx->width <= 0) {
41        av_log(avctx, AV_LOG_ERROR, "Invalid width or height\n");
42        return AVERROR_INVALIDDATA;
43    }
44
45    if (buf_size / avctx->height < avctx->width) {
46        av_log(avctx, AV_LOG_ERROR,
47               "Resolution larger than buffer size. Invalid header?\n");
48        return AVERROR_INVALIDDATA;
49    }
50
51    if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
52        return ret;
53    p->pict_type = AV_PICTURE_TYPE_I;
54    p->key_frame = 1;
55
56    init_get_bits(&gb, buf, buf_size * 8);
57
58    for (y = 0; y < avctx->height; y++) {
59        uint8_t *luma = &p->data[0][y * p->linesize[0]];
60        uint8_t *cb   = &p->data[1][y * p->linesize[1]];
61        uint8_t *cr   = &p->data[2][y * p->linesize[2]];
62        for (x = 0; x < avctx->width; x += 4) {
63            luma[3] = (get_bits(&gb, 5)*33) >> 2;
64            luma[2] = (get_bits(&gb, 5)*33) >> 2;
65            luma[1] = (get_bits(&gb, 5)*33) >> 2;
66            luma[0] = (get_bits(&gb, 5)*33) >> 2;
67            luma += 4;
68            *(cb++) = get_bits(&gb, 6) << 2;
69            *(cr++) = get_bits(&gb, 6) << 2;
70        }
71    }
72
73    *got_frame = 1;
74
75    return buf_size;
76}
77
78static av_cold int decode_init(AVCodecContext *avctx)
79{
80    avctx->pix_fmt = AV_PIX_FMT_YUV411P;
81    return 0;
82}
83
84const FFCodec ff_cljr_decoder = {
85    .p.name         = "cljr",
86    .p.long_name    = NULL_IF_CONFIG_SMALL("Cirrus Logic AccuPak"),
87    .p.type         = AVMEDIA_TYPE_VIDEO,
88    .p.id           = AV_CODEC_ID_CLJR,
89    .init           = decode_init,
90    FF_CODEC_DECODE_CB(decode_frame),
91    .p.capabilities = AV_CODEC_CAP_DR1,
92    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
93};
94
95