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
23 #include "bitstream.h"
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_end(AVCodecContext *avctx)
55 MotionPixelsContext *mp = avctx->priv_data;
57 av_freep(&mp->changes_map);
60 av_freep(&mp->bswapbuf);
61 av_frame_free(&mp->frame);
66 static av_cold int mp_decode_init(AVCodecContext *avctx)
68 MotionPixelsContext *mp = avctx->priv_data;
69 int w4 = (avctx->width + 3) & ~3;
70 int h4 = (avctx->height + 3) & ~3;
72 motionpixels_tableinit();
74 ff_bswapdsp_init(&mp->bdsp);
75 mp->changes_map = av_mallocz(avctx->width * h4);
76 mp->offset_bits_len = av_log2(avctx->width * avctx->height) + 1;
77 mp->vpt = av_mallocz(avctx->height * sizeof(YuvPixel));
78 mp->hpt = av_mallocz(h4 * w4 / 16 * sizeof(YuvPixel));
79 avctx->pix_fmt = AV_PIX_FMT_RGB555;
81 mp->frame = av_frame_alloc();
84 return AVERROR(ENOMEM);
90 static void mp_read_changes_map(MotionPixelsContext *mp, BitstreamContext *bc,
91 int count, int bits_len, int read_color)
94 int offset, w, h, color = 0, x, y, i;
97 offset = bitstream_read(bc, mp->offset_bits_len);
98 w = bitstream_read(bc, bits_len) + 1;
99 h = bitstream_read(bc, bits_len) + 1;
101 color = bitstream_read(bc, 15);
102 x = offset % mp->avctx->width;
103 y = offset / mp->avctx->width;
104 if (y >= mp->avctx->height)
106 w = FFMIN(w, mp->avctx->width - x);
107 h = FFMIN(h, mp->avctx->height - y);
108 pixels = (uint16_t *)&mp->frame->data[0][y * mp->frame->linesize[0] + x * 2];
110 mp->changes_map[offset] = w;
112 for (i = 0; i < w; ++i)
114 offset += mp->avctx->width;
115 pixels += mp->frame->linesize[0] / 2;
120 static void mp_get_code(MotionPixelsContext *mp, BitstreamContext *bc,
123 while (bitstream_read_bit(bc)) {
125 if (size > mp->max_codes_bits) {
126 av_log(mp->avctx, AV_LOG_ERROR, "invalid code size %d/%d\n", size, mp->max_codes_bits);
130 mp_get_code(mp, bc, size, code + 1);
132 if (mp->current_codes_count >= MAX_HUFF_CODES) {
133 av_log(mp->avctx, AV_LOG_ERROR, "too many codes\n");
136 mp->codes[mp->current_codes_count ].code = code;
137 mp->codes[mp->current_codes_count++].size = size;
140 static void mp_read_codes_table(MotionPixelsContext *mp, BitstreamContext *bc)
142 if (mp->codes_count == 1) {
143 mp->codes[0].delta = bitstream_read(bc, 4);
147 mp->max_codes_bits = bitstream_read(bc, 4);
148 for (i = 0; i < mp->codes_count; ++i)
149 mp->codes[i].delta = bitstream_read(bc, 4);
150 mp->current_codes_count = 0;
151 mp_get_code(mp, bc, 0, 0);
155 static int mp_gradient(MotionPixelsContext *mp, int component, int v)
159 delta = (v - 7) * mp->gradient_scale[component];
160 mp->gradient_scale[component] = (v == 0 || v == 14) ? 2 : 1;
164 static YuvPixel mp_get_yuv_from_rgb(MotionPixelsContext *mp, int x, int y)
168 color = *(uint16_t *)&mp->frame->data[0][y * mp->frame->linesize[0] + x * 2];
169 return mp_rgb_yuv_table[color];
172 static void mp_set_rgb_from_yuv(MotionPixelsContext *mp, int x, int y, const YuvPixel *p)
176 color = mp_yuv_to_rgb(p->y, p->v, p->u, 1);
177 *(uint16_t *)&mp->frame->data[0][y * mp->frame->linesize[0] + x * 2] = color;
180 static int mp_get_vlc(MotionPixelsContext *mp, BitstreamContext *bc)
184 i = (mp->codes_count == 1) ? 0 : bitstream_read_vlc(bc, mp->vlc.table, mp->max_codes_bits, 1);
185 i = FFMIN(i, FF_ARRAY_ELEMS(mp->codes) - 1);
186 return mp->codes[i].delta;
189 static void mp_decode_line(MotionPixelsContext *mp, BitstreamContext *bc, int y)
192 const int y0 = y * mp->avctx->width;
196 if (mp->changes_map[y0 + x] == 0) {
197 memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
200 while (x < mp->avctx->width) {
201 w = mp->changes_map[y0 + x];
204 if (mp->changes_map[y0 + x + mp->avctx->width] < w ||
205 mp->changes_map[y0 + x + mp->avctx->width * 2] < w ||
206 mp->changes_map[y0 + x + mp->avctx->width * 3] < w) {
207 for (i = (x + 3) & ~3; i < x + w; i += 4) {
208 mp->hpt[((y / 4) * mp->avctx->width + i) / 4] = mp_get_yuv_from_rgb(mp, i, y);
213 memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
214 p = mp_get_yuv_from_rgb(mp, x - 1, y);
216 p.y += mp_gradient(mp, 0, mp_get_vlc(mp, bc));
217 p.y = av_clip_uintp2(p.y, 5);
220 p.v += mp_gradient(mp, 1, mp_get_vlc(mp, bc));
221 p.v = av_clip_intp2(p.v, 5);
222 p.u += mp_gradient(mp, 2, mp_get_vlc(mp, bc));
223 p.u = av_clip_intp2(p.u, 5);
224 mp->hpt[((y / 4) * mp->avctx->width + x) / 4] = p;
226 p.v = mp->hpt[((y / 4) * mp->avctx->width + x) / 4].v;
227 p.u = mp->hpt[((y / 4) * mp->avctx->width + x) / 4].u;
230 mp_set_rgb_from_yuv(mp, x, y, &p);
236 static void mp_decode_frame_helper(MotionPixelsContext *mp,
237 BitstreamContext *bc)
242 for (y = 0; y < mp->avctx->height; ++y) {
243 if (mp->changes_map[y * mp->avctx->width] != 0) {
244 memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
245 p = mp_get_yuv_from_rgb(mp, 0, y);
247 p.y += mp_gradient(mp, 0, mp_get_vlc(mp, bc));
248 p.y = av_clip_uintp2(p.y, 5);
250 p.v += mp_gradient(mp, 1, mp_get_vlc(mp, bc));
251 p.v = av_clip_intp2(p.v, 5);
252 p.u += mp_gradient(mp, 2, mp_get_vlc(mp, bc));
253 p.u = av_clip_intp2(p.u, 5);
256 mp_set_rgb_from_yuv(mp, 0, y, &p);
259 for (y0 = 0; y0 < 2; ++y0)
260 for (y = y0; y < mp->avctx->height; y += 2)
261 mp_decode_line(mp, bc, y);
264 static int mp_decode_frame(AVCodecContext *avctx,
265 void *data, int *got_frame,
268 const uint8_t *buf = avpkt->data;
269 int buf_size = avpkt->size;
270 MotionPixelsContext *mp = avctx->priv_data;
272 int i, count1, count2, sz, ret;
274 if ((ret = ff_reget_buffer(avctx, mp->frame)) < 0) {
275 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
279 /* le32 bitstream msb first */
280 av_fast_malloc(&mp->bswapbuf, &mp->bswapbuf_size, buf_size + AV_INPUT_BUFFER_PADDING_SIZE);
282 return AVERROR(ENOMEM);
283 mp->bdsp.bswap_buf((uint32_t *) mp->bswapbuf, (const uint32_t *) buf,
286 memcpy(mp->bswapbuf + (buf_size & ~3), buf + (buf_size & ~3), buf_size & 3);
287 memset(mp->bswapbuf + buf_size, 0, AV_INPUT_BUFFER_PADDING_SIZE);
288 bitstream_init8(&bc, mp->bswapbuf, buf_size);
290 memset(mp->changes_map, 0, avctx->width * avctx->height);
291 for (i = !(avctx->extradata[1] & 2); i < 2; ++i) {
292 count1 = bitstream_read(&bc, 12);
293 count2 = bitstream_read(&bc, 12);
294 mp_read_changes_map(mp, &bc, count1, 8, i);
295 mp_read_changes_map(mp, &bc, count2, 4, i);
298 mp->codes_count = bitstream_read(&bc, 4);
299 if (mp->codes_count == 0)
302 if (mp->changes_map[0] == 0) {
303 *(uint16_t *)mp->frame->data[0] = bitstream_read(&bc, 15);
304 mp->changes_map[0] = 1;
306 mp_read_codes_table(mp, &bc);
308 sz = bitstream_read(&bc, 18);
309 if (avctx->extradata[0] != 5)
310 sz += bitstream_read(&bc, 18);
314 if (mp->max_codes_bits <= 0)
316 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))
318 mp_decode_frame_helper(mp, &bc);
319 ff_free_vlc(&mp->vlc);
322 if ((ret = av_frame_ref(data, mp->frame)) < 0)
328 AVCodec ff_motionpixels_decoder = {
329 .name = "motionpixels",
330 .long_name = NULL_IF_CONFIG_SMALL("Motion Pixels video"),
331 .type = AVMEDIA_TYPE_VIDEO,
332 .id = AV_CODEC_ID_MOTIONPIXELS,
333 .priv_data_size = sizeof(MotionPixelsContext),
334 .init = mp_decode_init,
335 .close = mp_decode_end,
336 .decode = mp_decode_frame,
337 .capabilities = AV_CODEC_CAP_DR1,