| 1 | /* |
| 2 | * huffyuv codec for libavcodec |
| 3 | * |
| 4 | * Copyright (c) 2002-2014 Michael Niedermayer <michaelni@gmx.at> |
| 5 | * |
| 6 | * see http://www.pcisys.net/~melanson/codecs/huffyuv.txt for a description of |
| 7 | * the algorithm used |
| 8 | * |
| 9 | * This file is part of FFmpeg. |
| 10 | * |
| 11 | * FFmpeg is free software; you can redistribute it and/or |
| 12 | * modify it under the terms of the GNU Lesser General Public |
| 13 | * License as published by the Free Software Foundation; either |
| 14 | * version 2.1 of the License, or (at your option) any later version. |
| 15 | * |
| 16 | * FFmpeg is distributed in the hope that it will be useful, |
| 17 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 18 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 19 | * Lesser General Public License for more details. |
| 20 | * |
| 21 | * You should have received a copy of the GNU Lesser General Public |
| 22 | * License along with FFmpeg; if not, write to the Free Software |
| 23 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 24 | */ |
| 25 | |
| 26 | /** |
| 27 | * @file |
| 28 | * huffyuv codec for libavcodec. |
| 29 | */ |
| 30 | |
| 31 | #include <stdint.h> |
| 32 | |
| 33 | #include "libavutil/mem.h" |
| 34 | |
| 35 | #include "avcodec.h" |
| 36 | #include "bswapdsp.h" |
| 37 | #include "huffyuv.h" |
| 38 | |
| 39 | int ff_huffyuv_generate_bits_table(uint32_t *dst, const uint8_t *len_table, int n) |
| 40 | { |
| 41 | int len, index; |
| 42 | uint32_t bits = 0; |
| 43 | |
| 44 | for (len = 32; len > 0; len--) { |
| 45 | for (index = 0; index < n; index++) { |
| 46 | if (len_table[index] == len) |
| 47 | dst[index] = bits++; |
| 48 | } |
| 49 | if (bits & 1) { |
| 50 | av_log(NULL, AV_LOG_ERROR, "Error generating huffman table\n"); |
| 51 | return -1; |
| 52 | } |
| 53 | bits >>= 1; |
| 54 | } |
| 55 | return 0; |
| 56 | } |
| 57 | |
| 58 | av_cold int ff_huffyuv_alloc_temp(HYuvContext *s) |
| 59 | { |
| 60 | int i; |
| 61 | |
| 62 | for (i=0; i<3; i++) { |
| 63 | s->temp[i]= av_malloc(4*s->width + 16); |
| 64 | if (!s->temp[i]) |
| 65 | return AVERROR(ENOMEM); |
| 66 | s->temp16[i] = (uint16_t*)s->temp[i]; |
| 67 | } |
| 68 | return 0; |
| 69 | } |
| 70 | |
| 71 | av_cold void ff_huffyuv_common_init(AVCodecContext *avctx) |
| 72 | { |
| 73 | HYuvContext *s = avctx->priv_data; |
| 74 | |
| 75 | s->avctx = avctx; |
| 76 | s->flags = avctx->flags; |
| 77 | |
| 78 | ff_bswapdsp_init(&s->bdsp); |
| 79 | ff_llviddsp_init(&s->llviddsp, avctx); |
| 80 | |
| 81 | s->width = avctx->width; |
| 82 | s->height = avctx->height; |
| 83 | |
| 84 | av_assert1(s->width > 0 && s->height > 0); |
| 85 | } |
| 86 | |
| 87 | av_cold void ff_huffyuv_common_end(HYuvContext *s) |
| 88 | { |
| 89 | int i; |
| 90 | |
| 91 | for(i = 0; i < 3; i++) { |
| 92 | av_freep(&s->temp[i]); |
| 93 | s->temp16[i] = NULL; |
| 94 | } |
| 95 | } |