| 1 | /* |
| 2 | * Miro VideoXL codec |
| 3 | * Copyright (c) 2004 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 | * Miro VideoXL codec. |
| 25 | */ |
| 26 | |
| 27 | #include "libavutil/common.h" |
| 28 | #include "libavutil/intreadwrite.h" |
| 29 | #include "avcodec.h" |
| 30 | #include "internal.h" |
| 31 | |
| 32 | static const int xl_table[32] = { |
| 33 | 0, 1, 2, 3, 4, 5, 6, 7, |
| 34 | 8, 9, 12, 15, 20, 25, 34, 46, |
| 35 | 64, 82, 94, 103, 108, 113, 116, 119, |
| 36 | 120, 121, 122, 123, 124, 125, 126, 127 |
| 37 | }; |
| 38 | |
| 39 | static int decode_frame(AVCodecContext *avctx, |
| 40 | void *data, int *got_frame, |
| 41 | AVPacket *avpkt) |
| 42 | { |
| 43 | const uint8_t *buf = avpkt->data; |
| 44 | int buf_size = avpkt->size; |
| 45 | AVFrame *const p = data; |
| 46 | uint8_t *Y, *U, *V; |
| 47 | int i, j, ret; |
| 48 | int stride; |
| 49 | uint32_t val; |
| 50 | int y0, y1, y2, y3 = 0, c0 = 0, c1 = 0; |
| 51 | |
| 52 | if (avctx->width % 4) { |
| 53 | av_log(avctx, AV_LOG_ERROR, "width is not a multiple of 4\n"); |
| 54 | return AVERROR_INVALIDDATA; |
| 55 | } |
| 56 | if (buf_size < avctx->width * avctx->height) { |
| 57 | av_log(avctx, AV_LOG_ERROR, "Packet is too small\n"); |
| 58 | return AVERROR_INVALIDDATA; |
| 59 | } |
| 60 | |
| 61 | if ((ret = ff_get_buffer(avctx, p, 0)) < 0) |
| 62 | return ret; |
| 63 | p->pict_type = AV_PICTURE_TYPE_I; |
| 64 | p->key_frame = 1; |
| 65 | |
| 66 | Y = p->data[0]; |
| 67 | U = p->data[1]; |
| 68 | V = p->data[2]; |
| 69 | |
| 70 | stride = avctx->width - 4; |
| 71 | |
| 72 | for (i = 0; i < avctx->height; i++) { |
| 73 | /* lines are stored in reversed order */ |
| 74 | buf += stride; |
| 75 | |
| 76 | for (j = 0; j < avctx->width; j += 4) { |
| 77 | /* value is stored in LE dword with word swapped */ |
| 78 | val = AV_RL32(buf); |
| 79 | buf -= 4; |
| 80 | val = ((val >> 16) & 0xFFFF) | ((val & 0xFFFF) << 16); |
| 81 | |
| 82 | if (!j) |
| 83 | y0 = (val & 0x1F) << 2; |
| 84 | else |
| 85 | y0 = y3 + xl_table[val & 0x1F]; |
| 86 | val >>= 5; |
| 87 | y1 = y0 + xl_table[val & 0x1F]; |
| 88 | val >>= 5; |
| 89 | y2 = y1 + xl_table[val & 0x1F]; |
| 90 | val >>= 6; /* align to word */ |
| 91 | y3 = y2 + xl_table[val & 0x1F]; |
| 92 | val >>= 5; |
| 93 | if (!j) |
| 94 | c0 = (val & 0x1F) << 2; |
| 95 | else |
| 96 | c0 += xl_table[val & 0x1F]; |
| 97 | val >>= 5; |
| 98 | if (!j) |
| 99 | c1 = (val & 0x1F) << 2; |
| 100 | else |
| 101 | c1 += xl_table[val & 0x1F]; |
| 102 | |
| 103 | Y[j + 0] = y0 << 1; |
| 104 | Y[j + 1] = y1 << 1; |
| 105 | Y[j + 2] = y2 << 1; |
| 106 | Y[j + 3] = y3 << 1; |
| 107 | |
| 108 | U[j >> 2] = c0 << 1; |
| 109 | V[j >> 2] = c1 << 1; |
| 110 | } |
| 111 | |
| 112 | buf += avctx->width + 4; |
| 113 | Y += p->linesize[0]; |
| 114 | U += p->linesize[1]; |
| 115 | V += p->linesize[2]; |
| 116 | } |
| 117 | |
| 118 | *got_frame = 1; |
| 119 | |
| 120 | return buf_size; |
| 121 | } |
| 122 | |
| 123 | static av_cold int decode_init(AVCodecContext *avctx) |
| 124 | { |
| 125 | avctx->pix_fmt = AV_PIX_FMT_YUV411P; |
| 126 | |
| 127 | return 0; |
| 128 | } |
| 129 | |
| 130 | AVCodec ff_xl_decoder = { |
| 131 | .name = "xl", |
| 132 | .long_name = NULL_IF_CONFIG_SMALL("Miro VideoXL"), |
| 133 | .type = AVMEDIA_TYPE_VIDEO, |
| 134 | .id = AV_CODEC_ID_VIXL, |
| 135 | .init = decode_init, |
| 136 | .decode = decode_frame, |
| 137 | .capabilities = CODEC_CAP_DR1, |
| 138 | }; |