Libav 0.7.1
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00001 /* 00002 * Motion Pixels Video Decoder 00003 * Copyright (c) 2008 Gregory Montoir (cyx@users.sourceforge.net) 00004 * 00005 * This file is part of Libav. 00006 * 00007 * Libav is free software; you can redistribute it and/or 00008 * modify it under the terms of the GNU Lesser General Public 00009 * License as published by the Free Software Foundation; either 00010 * version 2.1 of the License, or (at your option) any later version. 00011 * 00012 * Libav is distributed in the hope that it will be useful, 00013 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 00015 * Lesser General Public License for more details. 00016 * 00017 * You should have received a copy of the GNU Lesser General Public 00018 * License along with Libav; if not, write to the Free Software 00019 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 00020 */ 00021 00022 #include "avcodec.h" 00023 #include "get_bits.h" 00024 #include "dsputil.h" 00025 00026 #define MAX_HUFF_CODES 16 00027 00028 #include "motionpixels_tablegen.h" 00029 00030 typedef struct HuffCode { 00031 int code; 00032 uint8_t size; 00033 uint8_t delta; 00034 } HuffCode; 00035 00036 typedef struct MotionPixelsContext { 00037 AVCodecContext *avctx; 00038 AVFrame frame; 00039 DSPContext dsp; 00040 uint8_t *changes_map; 00041 int offset_bits_len; 00042 int codes_count, current_codes_count; 00043 int max_codes_bits; 00044 HuffCode codes[MAX_HUFF_CODES]; 00045 VLC vlc; 00046 YuvPixel *vpt, *hpt; 00047 uint8_t gradient_scale[3]; 00048 uint8_t *bswapbuf; 00049 int bswapbuf_size; 00050 } MotionPixelsContext; 00051 00052 static av_cold int mp_decode_init(AVCodecContext *avctx) 00053 { 00054 MotionPixelsContext *mp = avctx->priv_data; 00055 00056 motionpixels_tableinit(); 00057 mp->avctx = avctx; 00058 dsputil_init(&mp->dsp, avctx); 00059 mp->changes_map = av_mallocz(avctx->width * avctx->height); 00060 mp->offset_bits_len = av_log2(avctx->width * avctx->height) + 1; 00061 mp->vpt = av_mallocz(avctx->height * sizeof(YuvPixel)); 00062 mp->hpt = av_mallocz(avctx->height * avctx->width / 16 * sizeof(YuvPixel)); 00063 avctx->pix_fmt = PIX_FMT_RGB555; 00064 return 0; 00065 } 00066 00067 static void mp_read_changes_map(MotionPixelsContext *mp, GetBitContext *gb, int count, int bits_len, int read_color) 00068 { 00069 uint16_t *pixels; 00070 int offset, w, h, color = 0, x, y, i; 00071 00072 while (count--) { 00073 offset = get_bits_long(gb, mp->offset_bits_len); 00074 w = get_bits(gb, bits_len) + 1; 00075 h = get_bits(gb, bits_len) + 1; 00076 if (read_color) 00077 color = get_bits(gb, 15); 00078 x = offset % mp->avctx->width; 00079 y = offset / mp->avctx->width; 00080 if (y >= mp->avctx->height) 00081 continue; 00082 w = FFMIN(w, mp->avctx->width - x); 00083 h = FFMIN(h, mp->avctx->height - y); 00084 pixels = (uint16_t *)&mp->frame.data[0][y * mp->frame.linesize[0] + x * 2]; 00085 while (h--) { 00086 mp->changes_map[offset] = w; 00087 if (read_color) 00088 for (i = 0; i < w; ++i) 00089 pixels[i] = color; 00090 offset += mp->avctx->width; 00091 pixels += mp->frame.linesize[0] / 2; 00092 } 00093 } 00094 } 00095 00096 static void mp_get_code(MotionPixelsContext *mp, GetBitContext *gb, int size, int code) 00097 { 00098 while (get_bits1(gb)) { 00099 ++size; 00100 if (size > mp->max_codes_bits) { 00101 av_log(mp->avctx, AV_LOG_ERROR, "invalid code size %d/%d\n", size, mp->max_codes_bits); 00102 return; 00103 } 00104 code <<= 1; 00105 mp_get_code(mp, gb, size, code + 1); 00106 } 00107 if (mp->current_codes_count >= MAX_HUFF_CODES) { 00108 av_log(mp->avctx, AV_LOG_ERROR, "too many codes\n"); 00109 return; 00110 } 00111 mp->codes[mp->current_codes_count ].code = code; 00112 mp->codes[mp->current_codes_count++].size = size; 00113 } 00114 00115 static void mp_read_codes_table(MotionPixelsContext *mp, GetBitContext *gb) 00116 { 00117 if (mp->codes_count == 1) { 00118 mp->codes[0].delta = get_bits(gb, 4); 00119 } else { 00120 int i; 00121 00122 mp->max_codes_bits = get_bits(gb, 4); 00123 for (i = 0; i < mp->codes_count; ++i) 00124 mp->codes[i].delta = get_bits(gb, 4); 00125 mp->current_codes_count = 0; 00126 mp_get_code(mp, gb, 0, 0); 00127 } 00128 } 00129 00130 static int mp_gradient(MotionPixelsContext *mp, int component, int v) 00131 { 00132 int delta; 00133 00134 delta = (v - 7) * mp->gradient_scale[component]; 00135 mp->gradient_scale[component] = (v == 0 || v == 14) ? 2 : 1; 00136 return delta; 00137 } 00138 00139 static YuvPixel mp_get_yuv_from_rgb(MotionPixelsContext *mp, int x, int y) 00140 { 00141 int color; 00142 00143 color = *(uint16_t *)&mp->frame.data[0][y * mp->frame.linesize[0] + x * 2]; 00144 return mp_rgb_yuv_table[color]; 00145 } 00146 00147 static void mp_set_rgb_from_yuv(MotionPixelsContext *mp, int x, int y, const YuvPixel *p) 00148 { 00149 int color; 00150 00151 color = mp_yuv_to_rgb(p->y, p->v, p->u, 1); 00152 *(uint16_t *)&mp->frame.data[0][y * mp->frame.linesize[0] + x * 2] = color; 00153 } 00154 00155 static int mp_get_vlc(MotionPixelsContext *mp, GetBitContext *gb) 00156 { 00157 int i; 00158 00159 i = (mp->codes_count == 1) ? 0 : get_vlc2(gb, mp->vlc.table, mp->max_codes_bits, 1); 00160 return mp->codes[i].delta; 00161 } 00162 00163 static void mp_decode_line(MotionPixelsContext *mp, GetBitContext *gb, int y) 00164 { 00165 YuvPixel p; 00166 const int y0 = y * mp->avctx->width; 00167 int w, i, x = 0; 00168 00169 p = mp->vpt[y]; 00170 if (mp->changes_map[y0 + x] == 0) { 00171 memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale)); 00172 ++x; 00173 } 00174 while (x < mp->avctx->width) { 00175 w = mp->changes_map[y0 + x]; 00176 if (w != 0) { 00177 if ((y & 3) == 0) { 00178 if (mp->changes_map[y0 + x + mp->avctx->width] < w || 00179 mp->changes_map[y0 + x + mp->avctx->width * 2] < w || 00180 mp->changes_map[y0 + x + mp->avctx->width * 3] < w) { 00181 for (i = (x + 3) & ~3; i < x + w; i += 4) { 00182 mp->hpt[((y / 4) * mp->avctx->width + i) / 4] = mp_get_yuv_from_rgb(mp, i, y); 00183 } 00184 } 00185 } 00186 x += w; 00187 memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale)); 00188 p = mp_get_yuv_from_rgb(mp, x - 1, y); 00189 } else { 00190 p.y += mp_gradient(mp, 0, mp_get_vlc(mp, gb)); 00191 if ((x & 3) == 0) { 00192 if ((y & 3) == 0) { 00193 p.v += mp_gradient(mp, 1, mp_get_vlc(mp, gb)); 00194 p.u += mp_gradient(mp, 2, mp_get_vlc(mp, gb)); 00195 mp->hpt[((y / 4) * mp->avctx->width + x) / 4] = p; 00196 } else { 00197 p.v = mp->hpt[((y / 4) * mp->avctx->width + x) / 4].v; 00198 p.u = mp->hpt[((y / 4) * mp->avctx->width + x) / 4].u; 00199 } 00200 } 00201 mp_set_rgb_from_yuv(mp, x, y, &p); 00202 ++x; 00203 } 00204 } 00205 } 00206 00207 static void mp_decode_frame_helper(MotionPixelsContext *mp, GetBitContext *gb) 00208 { 00209 YuvPixel p; 00210 int y, y0; 00211 00212 for (y = 0; y < mp->avctx->height; ++y) { 00213 if (mp->changes_map[y * mp->avctx->width] != 0) { 00214 memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale)); 00215 p = mp_get_yuv_from_rgb(mp, 0, y); 00216 } else { 00217 p.y += mp_gradient(mp, 0, mp_get_vlc(mp, gb)); 00218 if ((y & 3) == 0) { 00219 p.v += mp_gradient(mp, 1, mp_get_vlc(mp, gb)); 00220 p.u += mp_gradient(mp, 2, mp_get_vlc(mp, gb)); 00221 } 00222 mp->vpt[y] = p; 00223 mp_set_rgb_from_yuv(mp, 0, y, &p); 00224 } 00225 } 00226 for (y0 = 0; y0 < 2; ++y0) 00227 for (y = y0; y < mp->avctx->height; y += 2) 00228 mp_decode_line(mp, gb, y); 00229 } 00230 00231 static int mp_decode_frame(AVCodecContext *avctx, 00232 void *data, int *data_size, 00233 AVPacket *avpkt) 00234 { 00235 const uint8_t *buf = avpkt->data; 00236 int buf_size = avpkt->size; 00237 MotionPixelsContext *mp = avctx->priv_data; 00238 GetBitContext gb; 00239 int i, count1, count2, sz; 00240 00241 mp->frame.reference = 1; 00242 mp->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE; 00243 if (avctx->reget_buffer(avctx, &mp->frame)) { 00244 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n"); 00245 return -1; 00246 } 00247 00248 /* le32 bitstream msb first */ 00249 av_fast_malloc(&mp->bswapbuf, &mp->bswapbuf_size, buf_size + FF_INPUT_BUFFER_PADDING_SIZE); 00250 if (!mp->bswapbuf) 00251 return AVERROR(ENOMEM); 00252 mp->dsp.bswap_buf((uint32_t *)mp->bswapbuf, (const uint32_t *)buf, buf_size / 4); 00253 if (buf_size & 3) 00254 memcpy(mp->bswapbuf + (buf_size & ~3), buf + (buf_size & ~3), buf_size & 3); 00255 init_get_bits(&gb, mp->bswapbuf, buf_size * 8); 00256 00257 memset(mp->changes_map, 0, avctx->width * avctx->height); 00258 for (i = !(avctx->extradata[1] & 2); i < 2; ++i) { 00259 count1 = get_bits(&gb, 12); 00260 count2 = get_bits(&gb, 12); 00261 mp_read_changes_map(mp, &gb, count1, 8, i); 00262 mp_read_changes_map(mp, &gb, count2, 4, i); 00263 } 00264 00265 mp->codes_count = get_bits(&gb, 4); 00266 if (mp->codes_count == 0) 00267 goto end; 00268 00269 if (mp->changes_map[0] == 0) { 00270 *(uint16_t *)mp->frame.data[0] = get_bits(&gb, 15); 00271 mp->changes_map[0] = 1; 00272 } 00273 mp_read_codes_table(mp, &gb); 00274 00275 sz = get_bits(&gb, 18); 00276 if (avctx->extradata[0] != 5) 00277 sz += get_bits(&gb, 18); 00278 if (sz == 0) 00279 goto end; 00280 00281 init_vlc(&mp->vlc, mp->max_codes_bits, mp->codes_count, &mp->codes[0].size, sizeof(HuffCode), 1, &mp->codes[0].code, sizeof(HuffCode), 4, 0); 00282 mp_decode_frame_helper(mp, &gb); 00283 free_vlc(&mp->vlc); 00284 00285 end: 00286 *data_size = sizeof(AVFrame); 00287 *(AVFrame *)data = mp->frame; 00288 return buf_size; 00289 } 00290 00291 static av_cold int mp_decode_end(AVCodecContext *avctx) 00292 { 00293 MotionPixelsContext *mp = avctx->priv_data; 00294 00295 av_freep(&mp->changes_map); 00296 av_freep(&mp->vpt); 00297 av_freep(&mp->hpt); 00298 av_freep(&mp->bswapbuf); 00299 if (mp->frame.data[0]) 00300 avctx->release_buffer(avctx, &mp->frame); 00301 00302 return 0; 00303 } 00304 00305 AVCodec ff_motionpixels_decoder = { 00306 "motionpixels", 00307 AVMEDIA_TYPE_VIDEO, 00308 CODEC_ID_MOTIONPIXELS, 00309 sizeof(MotionPixelsContext), 00310 mp_decode_init, 00311 NULL, 00312 mp_decode_end, 00313 mp_decode_frame, 00314 CODEC_CAP_DR1, 00315 .long_name = NULL_IF_CONFIG_SMALL("Motion Pixels video"), 00316 };