| 1 | /* |
| 2 | * Microsoft RLE video decoder |
| 3 | * Copyright (c) 2003 The FFmpeg Project |
| 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 | * MS RLE video decoder by Mike Melanson (melanson@pcisys.net) |
| 25 | * For more information about the MS RLE format, visit: |
| 26 | * http://www.pcisys.net/~melanson/codecs/ |
| 27 | * |
| 28 | * The MS RLE decoder outputs PAL8 colorspace data. |
| 29 | */ |
| 30 | |
| 31 | #include <stdio.h> |
| 32 | #include <stdlib.h> |
| 33 | #include <string.h> |
| 34 | |
| 35 | #include "avcodec.h" |
| 36 | #include "internal.h" |
| 37 | #include "msrledec.h" |
| 38 | #include "libavutil/imgutils.h" |
| 39 | |
| 40 | typedef struct MsrleContext { |
| 41 | AVCodecContext *avctx; |
| 42 | AVFrame *frame; |
| 43 | |
| 44 | GetByteContext gb; |
| 45 | const unsigned char *buf; |
| 46 | int size; |
| 47 | |
| 48 | uint32_t pal[256]; |
| 49 | } MsrleContext; |
| 50 | |
| 51 | static av_cold int msrle_decode_init(AVCodecContext *avctx) |
| 52 | { |
| 53 | MsrleContext *s = avctx->priv_data; |
| 54 | int i; |
| 55 | |
| 56 | s->avctx = avctx; |
| 57 | |
| 58 | switch (avctx->bits_per_coded_sample) { |
| 59 | case 1: |
| 60 | avctx->pix_fmt = AV_PIX_FMT_MONOWHITE; |
| 61 | break; |
| 62 | case 4: |
| 63 | case 8: |
| 64 | avctx->pix_fmt = AV_PIX_FMT_PAL8; |
| 65 | break; |
| 66 | case 24: |
| 67 | avctx->pix_fmt = AV_PIX_FMT_BGR24; |
| 68 | break; |
| 69 | default: |
| 70 | av_log(avctx, AV_LOG_ERROR, "unsupported bits per sample\n"); |
| 71 | return AVERROR_INVALIDDATA; |
| 72 | } |
| 73 | |
| 74 | s->frame = av_frame_alloc(); |
| 75 | if (!s->frame) |
| 76 | return AVERROR(ENOMEM); |
| 77 | |
| 78 | if (avctx->extradata_size >= 4) |
| 79 | for (i = 0; i < FFMIN(avctx->extradata_size, AVPALETTE_SIZE)/4; i++) |
| 80 | s->pal[i] = 0xFFU<<24 | AV_RL32(avctx->extradata+4*i); |
| 81 | |
| 82 | return 0; |
| 83 | } |
| 84 | |
| 85 | static int msrle_decode_frame(AVCodecContext *avctx, |
| 86 | void *data, int *got_frame, |
| 87 | AVPacket *avpkt) |
| 88 | { |
| 89 | const uint8_t *buf = avpkt->data; |
| 90 | int buf_size = avpkt->size; |
| 91 | MsrleContext *s = avctx->priv_data; |
| 92 | int istride = FFALIGN(avctx->width*avctx->bits_per_coded_sample, 32) / 8; |
| 93 | int ret; |
| 94 | |
| 95 | s->buf = buf; |
| 96 | s->size = buf_size; |
| 97 | |
| 98 | if ((ret = ff_reget_buffer(avctx, s->frame)) < 0) |
| 99 | return ret; |
| 100 | |
| 101 | if (avctx->bits_per_coded_sample > 1 && avctx->bits_per_coded_sample <= 8) { |
| 102 | const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL); |
| 103 | |
| 104 | if (pal) { |
| 105 | s->frame->palette_has_changed = 1; |
| 106 | memcpy(s->pal, pal, AVPALETTE_SIZE); |
| 107 | } |
| 108 | /* make the palette available */ |
| 109 | memcpy(s->frame->data[1], s->pal, AVPALETTE_SIZE); |
| 110 | } |
| 111 | |
| 112 | /* FIXME how to correctly detect RLE ??? */ |
| 113 | if (avctx->height * istride == avpkt->size) { /* assume uncompressed */ |
| 114 | int linesize = av_image_get_linesize(avctx->pix_fmt, avctx->width, 0); |
| 115 | uint8_t *ptr = s->frame->data[0]; |
| 116 | uint8_t *buf = avpkt->data + (avctx->height-1)*istride; |
| 117 | int i, j; |
| 118 | |
| 119 | if (linesize < 0) |
| 120 | return linesize; |
| 121 | |
| 122 | for (i = 0; i < avctx->height; i++) { |
| 123 | if (avctx->bits_per_coded_sample == 4) { |
| 124 | for (j = 0; j < avctx->width - 1; j += 2) { |
| 125 | ptr[j+0] = buf[j>>1] >> 4; |
| 126 | ptr[j+1] = buf[j>>1] & 0xF; |
| 127 | } |
| 128 | if (avctx->width & 1) |
| 129 | ptr[j+0] = buf[j>>1] >> 4; |
| 130 | } else { |
| 131 | memcpy(ptr, buf, linesize); |
| 132 | } |
| 133 | buf -= istride; |
| 134 | ptr += s->frame->linesize[0]; |
| 135 | } |
| 136 | } else { |
| 137 | bytestream2_init(&s->gb, buf, buf_size); |
| 138 | ff_msrle_decode(avctx, (AVPicture*)s->frame, avctx->bits_per_coded_sample, &s->gb); |
| 139 | } |
| 140 | |
| 141 | if ((ret = av_frame_ref(data, s->frame)) < 0) |
| 142 | return ret; |
| 143 | |
| 144 | *got_frame = 1; |
| 145 | |
| 146 | /* report that the buffer was completely consumed */ |
| 147 | return buf_size; |
| 148 | } |
| 149 | |
| 150 | static av_cold int msrle_decode_end(AVCodecContext *avctx) |
| 151 | { |
| 152 | MsrleContext *s = avctx->priv_data; |
| 153 | |
| 154 | /* release the last frame */ |
| 155 | av_frame_free(&s->frame); |
| 156 | |
| 157 | return 0; |
| 158 | } |
| 159 | |
| 160 | AVCodec ff_msrle_decoder = { |
| 161 | .name = "msrle", |
| 162 | .long_name = NULL_IF_CONFIG_SMALL("Microsoft RLE"), |
| 163 | .type = AVMEDIA_TYPE_VIDEO, |
| 164 | .id = AV_CODEC_ID_MSRLE, |
| 165 | .priv_data_size = sizeof(MsrleContext), |
| 166 | .init = msrle_decode_init, |
| 167 | .close = msrle_decode_end, |
| 168 | .decode = msrle_decode_frame, |
| 169 | .capabilities = CODEC_CAP_DR1, |
| 170 | }; |