2 * Motion Pixels Video Decoder
3 * Copyright (c) 2008 Gregory Montoir (cyx@users.sourceforge.net)
5 * This file is part of Libav.
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.
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.
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
27 #define MAX_HUFF_CODES 16
29 #include "motionpixels_tablegen.h"
31 typedef struct HuffCode {
37 typedef struct MotionPixelsContext {
38 AVCodecContext *avctx;
43 int codes_count, current_codes_count;
45 HuffCode codes[MAX_HUFF_CODES];
48 uint8_t gradient_scale[3];
51 } MotionPixelsContext;
53 static av_cold int mp_decode_init(AVCodecContext *avctx)
55 MotionPixelsContext *mp = avctx->priv_data;
56 int w4 = (avctx->width + 3) & ~3;
57 int h4 = (avctx->height + 3) & ~3;
59 motionpixels_tableinit();
61 ff_dsputil_init(&mp->dsp, avctx);
62 mp->changes_map = av_mallocz(avctx->width * h4);
63 mp->offset_bits_len = av_log2(avctx->width * avctx->height) + 1;
64 mp->vpt = av_mallocz(avctx->height * sizeof(YuvPixel));
65 mp->hpt = av_mallocz(h4 * w4 / 16 * sizeof(YuvPixel));
66 avctx->pix_fmt = AV_PIX_FMT_RGB555;
67 avcodec_get_frame_defaults(&mp->frame);
71 static void mp_read_changes_map(MotionPixelsContext *mp, GetBitContext *gb, int count, int bits_len, int read_color)
74 int offset, w, h, color = 0, x, y, i;
77 offset = get_bits_long(gb, mp->offset_bits_len);
78 w = get_bits(gb, bits_len) + 1;
79 h = get_bits(gb, bits_len) + 1;
81 color = get_bits(gb, 15);
82 x = offset % mp->avctx->width;
83 y = offset / mp->avctx->width;
84 if (y >= mp->avctx->height)
86 w = FFMIN(w, mp->avctx->width - x);
87 h = FFMIN(h, mp->avctx->height - y);
88 pixels = (uint16_t *)&mp->frame.data[0][y * mp->frame.linesize[0] + x * 2];
90 mp->changes_map[offset] = w;
92 for (i = 0; i < w; ++i)
94 offset += mp->avctx->width;
95 pixels += mp->frame.linesize[0] / 2;
100 static void mp_get_code(MotionPixelsContext *mp, GetBitContext *gb, int size, int code)
102 while (get_bits1(gb)) {
104 if (size > mp->max_codes_bits) {
105 av_log(mp->avctx, AV_LOG_ERROR, "invalid code size %d/%d\n", size, mp->max_codes_bits);
109 mp_get_code(mp, gb, size, code + 1);
111 if (mp->current_codes_count >= MAX_HUFF_CODES) {
112 av_log(mp->avctx, AV_LOG_ERROR, "too many codes\n");
115 mp->codes[mp->current_codes_count ].code = code;
116 mp->codes[mp->current_codes_count++].size = size;
119 static void mp_read_codes_table(MotionPixelsContext *mp, GetBitContext *gb)
121 if (mp->codes_count == 1) {
122 mp->codes[0].delta = get_bits(gb, 4);
126 mp->max_codes_bits = get_bits(gb, 4);
127 for (i = 0; i < mp->codes_count; ++i)
128 mp->codes[i].delta = get_bits(gb, 4);
129 mp->current_codes_count = 0;
130 mp_get_code(mp, gb, 0, 0);
134 static int mp_gradient(MotionPixelsContext *mp, int component, int v)
138 delta = (v - 7) * mp->gradient_scale[component];
139 mp->gradient_scale[component] = (v == 0 || v == 14) ? 2 : 1;
143 static YuvPixel mp_get_yuv_from_rgb(MotionPixelsContext *mp, int x, int y)
147 color = *(uint16_t *)&mp->frame.data[0][y * mp->frame.linesize[0] + x * 2];
148 return mp_rgb_yuv_table[color];
151 static void mp_set_rgb_from_yuv(MotionPixelsContext *mp, int x, int y, const YuvPixel *p)
155 color = mp_yuv_to_rgb(p->y, p->v, p->u, 1);
156 *(uint16_t *)&mp->frame.data[0][y * mp->frame.linesize[0] + x * 2] = color;
159 static int mp_get_vlc(MotionPixelsContext *mp, GetBitContext *gb)
163 i = (mp->codes_count == 1) ? 0 : get_vlc2(gb, mp->vlc.table, mp->max_codes_bits, 1);
164 return mp->codes[i].delta;
167 static void mp_decode_line(MotionPixelsContext *mp, GetBitContext *gb, int y)
170 const int y0 = y * mp->avctx->width;
174 if (mp->changes_map[y0 + x] == 0) {
175 memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
178 while (x < mp->avctx->width) {
179 w = mp->changes_map[y0 + x];
182 if (mp->changes_map[y0 + x + mp->avctx->width] < w ||
183 mp->changes_map[y0 + x + mp->avctx->width * 2] < w ||
184 mp->changes_map[y0 + x + mp->avctx->width * 3] < w) {
185 for (i = (x + 3) & ~3; i < x + w; i += 4) {
186 mp->hpt[((y / 4) * mp->avctx->width + i) / 4] = mp_get_yuv_from_rgb(mp, i, y);
191 memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
192 p = mp_get_yuv_from_rgb(mp, x - 1, y);
194 p.y += mp_gradient(mp, 0, mp_get_vlc(mp, gb));
195 p.y = av_clip(p.y, 0, 31);
198 p.v += mp_gradient(mp, 1, mp_get_vlc(mp, gb));
199 p.v = av_clip(p.v, -32, 31);
200 p.u += mp_gradient(mp, 2, mp_get_vlc(mp, gb));
201 p.u = av_clip(p.u, -32, 31);
202 mp->hpt[((y / 4) * mp->avctx->width + x) / 4] = p;
204 p.v = mp->hpt[((y / 4) * mp->avctx->width + x) / 4].v;
205 p.u = mp->hpt[((y / 4) * mp->avctx->width + x) / 4].u;
208 mp_set_rgb_from_yuv(mp, x, y, &p);
214 static void mp_decode_frame_helper(MotionPixelsContext *mp, GetBitContext *gb)
219 for (y = 0; y < mp->avctx->height; ++y) {
220 if (mp->changes_map[y * mp->avctx->width] != 0) {
221 memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
222 p = mp_get_yuv_from_rgb(mp, 0, y);
224 p.y += mp_gradient(mp, 0, mp_get_vlc(mp, gb));
225 p.y = av_clip(p.y, 0, 31);
227 p.v += mp_gradient(mp, 1, mp_get_vlc(mp, gb));
228 p.v = av_clip(p.v, -32, 31);
229 p.u += mp_gradient(mp, 2, mp_get_vlc(mp, gb));
230 p.u = av_clip(p.u, -32, 31);
233 mp_set_rgb_from_yuv(mp, 0, y, &p);
236 for (y0 = 0; y0 < 2; ++y0)
237 for (y = y0; y < mp->avctx->height; y += 2)
238 mp_decode_line(mp, gb, y);
241 static int mp_decode_frame(AVCodecContext *avctx,
242 void *data, int *got_frame,
245 const uint8_t *buf = avpkt->data;
246 int buf_size = avpkt->size;
247 MotionPixelsContext *mp = avctx->priv_data;
249 int i, count1, count2, sz, ret;
251 if ((ret = ff_reget_buffer(avctx, &mp->frame)) < 0) {
252 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
256 /* le32 bitstream msb first */
257 av_fast_malloc(&mp->bswapbuf, &mp->bswapbuf_size, buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
259 return AVERROR(ENOMEM);
260 mp->dsp.bswap_buf((uint32_t *)mp->bswapbuf, (const uint32_t *)buf, buf_size / 4);
262 memcpy(mp->bswapbuf + (buf_size & ~3), buf + (buf_size & ~3), buf_size & 3);
263 memset(mp->bswapbuf + buf_size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
264 init_get_bits(&gb, mp->bswapbuf, buf_size * 8);
266 memset(mp->changes_map, 0, avctx->width * avctx->height);
267 for (i = !(avctx->extradata[1] & 2); i < 2; ++i) {
268 count1 = get_bits(&gb, 12);
269 count2 = get_bits(&gb, 12);
270 mp_read_changes_map(mp, &gb, count1, 8, i);
271 mp_read_changes_map(mp, &gb, count2, 4, i);
274 mp->codes_count = get_bits(&gb, 4);
275 if (mp->codes_count == 0)
278 if (mp->changes_map[0] == 0) {
279 *(uint16_t *)mp->frame.data[0] = get_bits(&gb, 15);
280 mp->changes_map[0] = 1;
282 mp_read_codes_table(mp, &gb);
284 sz = get_bits(&gb, 18);
285 if (avctx->extradata[0] != 5)
286 sz += get_bits(&gb, 18);
290 if (mp->max_codes_bits <= 0)
292 if (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))
294 mp_decode_frame_helper(mp, &gb);
295 ff_free_vlc(&mp->vlc);
298 if ((ret = av_frame_ref(data, &mp->frame)) < 0)
304 static av_cold int mp_decode_end(AVCodecContext *avctx)
306 MotionPixelsContext *mp = avctx->priv_data;
308 av_freep(&mp->changes_map);
311 av_freep(&mp->bswapbuf);
312 av_frame_unref(&mp->frame);
317 AVCodec ff_motionpixels_decoder = {
318 .name = "motionpixels",
319 .type = AVMEDIA_TYPE_VIDEO,
320 .id = AV_CODEC_ID_MOTIONPIXELS,
321 .priv_data_size = sizeof(MotionPixelsContext),
322 .init = mp_decode_init,
323 .close = mp_decode_end,
324 .decode = mp_decode_frame,
325 .capabilities = CODEC_CAP_DR1,
326 .long_name = NULL_IF_CONFIG_SMALL("Motion Pixels video"),