1/* 2 * Bitmap Brothers JV video decoder 3 * Copyright (c) 2011 Peter Ross <pross@xvid.org> 4 * 5 * This file is part of Libav. 6 * 7 * Libav 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 * Libav 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 Libav; 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 * Bitmap Brothers JV video decoder 25 * @author Peter Ross <pross@xvid.org> 26 */ 27 28#include "avcodec.h" 29#include "dsputil.h" 30#include "get_bits.h" 31#include "libavutil/intreadwrite.h" 32 33typedef struct JvContext { 34 DSPContext dsp; 35 AVFrame frame; 36 uint32_t palette[AVPALETTE_COUNT]; 37 int palette_has_changed; 38} JvContext; 39 40static av_cold int decode_init(AVCodecContext *avctx) 41{ 42 JvContext *s = avctx->priv_data; 43 avctx->pix_fmt = PIX_FMT_PAL8; 44 dsputil_init(&s->dsp, avctx); 45 return 0; 46} 47 48/** 49 * Decode 2x2 block 50 */ 51static inline void decode2x2(GetBitContext *gb, uint8_t *dst, int linesize) 52{ 53 int i, j, v[2]; 54 55 switch (get_bits(gb, 2)) { 56 case 1: 57 v[0] = get_bits(gb, 8); 58 for (j = 0; j < 2; j++) 59 memset(dst + j*linesize, v[0], 2); 60 break; 61 case 2: 62 v[0] = get_bits(gb, 8); 63 v[1] = get_bits(gb, 8); 64 for (j = 0; j < 2; j++) 65 for (i = 0; i < 2; i++) 66 dst[j*linesize + i] = v[get_bits1(gb)]; 67 break; 68 case 3: 69 for (j = 0; j < 2; j++) 70 for (i = 0; i < 2; i++) 71 dst[j*linesize + i] = get_bits(gb, 8); 72 } 73} 74 75/** 76 * Decode 4x4 block 77 */ 78static inline void decode4x4(GetBitContext *gb, uint8_t *dst, int linesize) 79{ 80 int i, j, v[2]; 81 82 switch (get_bits(gb, 2)) { 83 case 1: 84 v[0] = get_bits(gb, 8); 85 for (j = 0; j < 4; j++) 86 memset(dst + j*linesize, v[0], 4); 87 break; 88 case 2: 89 v[0] = get_bits(gb, 8); 90 v[1] = get_bits(gb, 8); 91 for (j = 2; j >= 0; j -= 2) { 92 for (i = 0; i < 4; i++) 93 dst[j*linesize + i] = v[get_bits1(gb)]; 94 for (i = 0; i < 4; i++) 95 dst[(j+1)*linesize + i] = v[get_bits1(gb)]; 96 } 97 break; 98 case 3: 99 for (j = 0; j < 4; j += 2) 100 for (i = 0; i < 4; i += 2) 101 decode2x2(gb, dst + j*linesize + i, linesize); 102 } 103} 104 105/** 106 * Decode 8x8 block 107 */ 108static inline void decode8x8(GetBitContext *gb, uint8_t *dst, int linesize, DSPContext *dsp) 109{ 110 int i, j, v[2]; 111 112 switch (get_bits(gb, 2)) { 113 case 1: 114 v[0] = get_bits(gb, 8); 115 dsp->fill_block_tab[1](dst, v[0], linesize, 8); 116 break; 117 case 2: 118 v[0] = get_bits(gb, 8); 119 v[1] = get_bits(gb, 8); 120 for (j = 7; j >= 0; j--) 121 for (i = 0; i < 8; i++) 122 dst[j*linesize + i] = v[get_bits1(gb)]; 123 break; 124 case 3: 125 for (j = 0; j < 8; j += 4) 126 for (i = 0; i < 8; i += 4) 127 decode4x4(gb, dst + j*linesize + i, linesize); 128 } 129} 130 131static int decode_frame(AVCodecContext *avctx, 132 void *data, int *data_size, 133 AVPacket *avpkt) 134{ 135 JvContext *s = avctx->priv_data; 136 int buf_size = avpkt->size; 137 const uint8_t *buf = avpkt->data; 138 const uint8_t *buf_end = buf + buf_size; 139 int video_size, video_type, i, j; 140 141 video_size = AV_RL32(buf); 142 video_type = buf[4]; 143 buf += 5; 144 145 if (video_size) { 146 if (avctx->reget_buffer(avctx, &s->frame) < 0) { 147 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); 148 return -1; 149 } 150 151 if (video_type == 0 || video_type == 1) { 152 GetBitContext gb; 153 init_get_bits(&gb, buf, 8 * FFMIN(video_size, buf_end - buf)); 154 155 for (j = 0; j < avctx->height; j += 8) 156 for (i = 0; i < avctx->width; i += 8) 157 decode8x8(&gb, s->frame.data[0] + j*s->frame.linesize[0] + i, 158 s->frame.linesize[0], &s->dsp); 159 160 buf += video_size; 161 } else if (video_type == 2) { 162 if (buf + 1 <= buf_end) { 163 int v = *buf++; 164 for (j = 0; j < avctx->height; j++) 165 memset(s->frame.data[0] + j*s->frame.linesize[0], v, avctx->width); 166 } 167 } else { 168 av_log(avctx, AV_LOG_WARNING, "unsupported frame type %i\n", video_type); 169 return AVERROR_INVALIDDATA; 170 } 171 } 172 173 if (buf < buf_end) { 174 for (i = 0; i < AVPALETTE_COUNT && buf + 3 <= buf_end; i++) { 175 s->palette[i] = AV_RB24(buf) << 2; 176 buf += 3; 177 } 178 s->palette_has_changed = 1; 179 } 180 181 if (video_size) { 182 s->frame.key_frame = 1; 183 s->frame.pict_type = AV_PICTURE_TYPE_I; 184 s->frame.palette_has_changed = s->palette_has_changed; 185 s->palette_has_changed = 0; 186 memcpy(s->frame.data[1], s->palette, AVPALETTE_SIZE); 187 188 *data_size = sizeof(AVFrame); 189 *(AVFrame*)data = s->frame; 190 } 191 192 return buf_size; 193} 194 195static av_cold int decode_close(AVCodecContext *avctx) 196{ 197 JvContext *s = avctx->priv_data; 198 199 if(s->frame.data[0]) 200 avctx->release_buffer(avctx, &s->frame); 201 202 return 0; 203} 204 205AVCodec ff_jv_decoder = { 206 .name = "jv", 207 .long_name = NULL_IF_CONFIG_SMALL("Bitmap Brothers JV video"), 208 .type = AVMEDIA_TYPE_VIDEO, 209 .id = CODEC_ID_JV, 210 .priv_data_size = sizeof(JvContext), 211 .init = decode_init, 212 .close = decode_close, 213 .decode = decode_frame, 214 .capabilities = CODEC_CAP_DR1, 215}; 216