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"
28 #define MAX_HUFF_CODES 16
30 #include "motionpixels_tablegen.h"
32 typedef struct HuffCode {
38 typedef struct MotionPixelsContext {
39 AVCodecContext *avctx;
44 int codes_count, current_codes_count;
46 HuffCode codes[MAX_HUFF_CODES];
49 uint8_t gradient_scale[3];
52 } MotionPixelsContext;
54 static av_cold int mp_decode_end(AVCodecContext *avctx)
56 MotionPixelsContext *mp = avctx->priv_data;
58 av_freep(&mp->changes_map);
61 av_freep(&mp->bswapbuf);
62 av_frame_free(&mp->frame);
67 static av_cold int mp_decode_init(AVCodecContext *avctx)
69 MotionPixelsContext *mp = avctx->priv_data;
70 int w4 = (avctx->width + 3) & ~3;
71 int h4 = (avctx->height + 3) & ~3;
73 motionpixels_tableinit();
75 ff_bswapdsp_init(&mp->bdsp);
76 mp->changes_map = av_mallocz(avctx->width * h4);
77 mp->offset_bits_len = av_log2(avctx->width * avctx->height) + 1;
78 mp->vpt = av_mallocz(avctx->height * sizeof(YuvPixel));
79 mp->hpt = av_mallocz(h4 * w4 / 16 * sizeof(YuvPixel));
80 avctx->pix_fmt = AV_PIX_FMT_RGB555;
82 mp->frame = av_frame_alloc();
85 return AVERROR(ENOMEM);
91 static void mp_read_changes_map(MotionPixelsContext *mp, BitstreamContext *bc,
92 int count, int bits_len, int read_color)
95 int offset, w, h, color = 0, x, y, i;
98 offset = bitstream_read(bc, mp->offset_bits_len);
99 w = bitstream_read(bc, bits_len) + 1;
100 h = bitstream_read(bc, bits_len) + 1;
102 color = bitstream_read(bc, 15);
103 x = offset % mp->avctx->width;
104 y = offset / mp->avctx->width;
105 if (y >= mp->avctx->height)
107 w = FFMIN(w, mp->avctx->width - x);
108 h = FFMIN(h, mp->avctx->height - y);
109 pixels = (uint16_t *)&mp->frame->data[0][y * mp->frame->linesize[0] + x * 2];
111 mp->changes_map[offset] = w;
113 for (i = 0; i < w; ++i)
115 offset += mp->avctx->width;
116 pixels += mp->frame->linesize[0] / 2;
121 static void mp_get_code(MotionPixelsContext *mp, BitstreamContext *bc,
124 while (bitstream_read_bit(bc)) {
126 if (size > mp->max_codes_bits) {
127 av_log(mp->avctx, AV_LOG_ERROR, "invalid code size %d/%d\n", size, mp->max_codes_bits);
131 mp_get_code(mp, bc, size, code + 1);
133 if (mp->current_codes_count >= MAX_HUFF_CODES) {
134 av_log(mp->avctx, AV_LOG_ERROR, "too many codes\n");
137 mp->codes[mp->current_codes_count ].code = code;
138 mp->codes[mp->current_codes_count++].size = size;
141 static void mp_read_codes_table(MotionPixelsContext *mp, BitstreamContext *bc)
143 if (mp->codes_count == 1) {
144 mp->codes[0].delta = bitstream_read(bc, 4);
148 mp->max_codes_bits = bitstream_read(bc, 4);
149 for (i = 0; i < mp->codes_count; ++i)
150 mp->codes[i].delta = bitstream_read(bc, 4);
151 mp->current_codes_count = 0;
152 mp_get_code(mp, bc, 0, 0);
156 static int mp_gradient(MotionPixelsContext *mp, int component, int v)
160 delta = (v - 7) * mp->gradient_scale[component];
161 mp->gradient_scale[component] = (v == 0 || v == 14) ? 2 : 1;
165 static YuvPixel mp_get_yuv_from_rgb(MotionPixelsContext *mp, int x, int y)
169 color = *(uint16_t *)&mp->frame->data[0][y * mp->frame->linesize[0] + x * 2];
170 return mp_rgb_yuv_table[color];
173 static void mp_set_rgb_from_yuv(MotionPixelsContext *mp, int x, int y, const YuvPixel *p)
177 color = mp_yuv_to_rgb(p->y, p->v, p->u, 1);
178 *(uint16_t *)&mp->frame->data[0][y * mp->frame->linesize[0] + x * 2] = color;
181 static int mp_get_vlc(MotionPixelsContext *mp, BitstreamContext *bc)
185 i = (mp->codes_count == 1) ? 0 : bitstream_read_vlc(bc, mp->vlc.table, mp->max_codes_bits, 1);
186 i = FFMIN(i, FF_ARRAY_ELEMS(mp->codes) - 1);
187 return mp->codes[i].delta;
190 static void mp_decode_line(MotionPixelsContext *mp, BitstreamContext *bc, int y)
193 const int y0 = y * mp->avctx->width;
197 if (mp->changes_map[y0 + x] == 0) {
198 memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
201 while (x < mp->avctx->width) {
202 w = mp->changes_map[y0 + x];
205 if (mp->changes_map[y0 + x + mp->avctx->width] < w ||
206 mp->changes_map[y0 + x + mp->avctx->width * 2] < w ||
207 mp->changes_map[y0 + x + mp->avctx->width * 3] < w) {
208 for (i = (x + 3) & ~3; i < x + w; i += 4) {
209 mp->hpt[((y / 4) * mp->avctx->width + i) / 4] = mp_get_yuv_from_rgb(mp, i, y);
214 memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
215 p = mp_get_yuv_from_rgb(mp, x - 1, y);
217 p.y += mp_gradient(mp, 0, mp_get_vlc(mp, bc));
218 p.y = av_clip_uintp2(p.y, 5);
221 p.v += mp_gradient(mp, 1, mp_get_vlc(mp, bc));
222 p.v = av_clip_intp2(p.v, 5);
223 p.u += mp_gradient(mp, 2, mp_get_vlc(mp, bc));
224 p.u = av_clip_intp2(p.u, 5);
225 mp->hpt[((y / 4) * mp->avctx->width + x) / 4] = p;
227 p.v = mp->hpt[((y / 4) * mp->avctx->width + x) / 4].v;
228 p.u = mp->hpt[((y / 4) * mp->avctx->width + x) / 4].u;
231 mp_set_rgb_from_yuv(mp, x, y, &p);
237 static void mp_decode_frame_helper(MotionPixelsContext *mp,
238 BitstreamContext *bc)
243 for (y = 0; y < mp->avctx->height; ++y) {
244 if (mp->changes_map[y * mp->avctx->width] != 0) {
245 memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
246 p = mp_get_yuv_from_rgb(mp, 0, y);
248 p.y += mp_gradient(mp, 0, mp_get_vlc(mp, bc));
249 p.y = av_clip_uintp2(p.y, 5);
251 p.v += mp_gradient(mp, 1, mp_get_vlc(mp, bc));
252 p.v = av_clip_intp2(p.v, 5);
253 p.u += mp_gradient(mp, 2, mp_get_vlc(mp, bc));
254 p.u = av_clip_intp2(p.u, 5);
257 mp_set_rgb_from_yuv(mp, 0, y, &p);
260 for (y0 = 0; y0 < 2; ++y0)
261 for (y = y0; y < mp->avctx->height; y += 2)
262 mp_decode_line(mp, bc, y);
265 static int mp_decode_frame(AVCodecContext *avctx,
266 void *data, int *got_frame,
269 const uint8_t *buf = avpkt->data;
270 int buf_size = avpkt->size;
271 MotionPixelsContext *mp = avctx->priv_data;
273 int i, count1, count2, sz, ret;
275 if ((ret = ff_reget_buffer(avctx, mp->frame)) < 0) {
276 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
280 /* le32 bitstream msb first */
281 av_fast_malloc(&mp->bswapbuf, &mp->bswapbuf_size, buf_size + AV_INPUT_BUFFER_PADDING_SIZE);
283 return AVERROR(ENOMEM);
284 mp->bdsp.bswap_buf((uint32_t *) mp->bswapbuf, (const uint32_t *) buf,
287 memcpy(mp->bswapbuf + (buf_size & ~3), buf + (buf_size & ~3), buf_size & 3);
288 memset(mp->bswapbuf + buf_size, 0, AV_INPUT_BUFFER_PADDING_SIZE);
289 bitstream_init8(&bc, mp->bswapbuf, buf_size);
291 memset(mp->changes_map, 0, avctx->width * avctx->height);
292 for (i = !(avctx->extradata[1] & 2); i < 2; ++i) {
293 count1 = bitstream_read(&bc, 12);
294 count2 = bitstream_read(&bc, 12);
295 mp_read_changes_map(mp, &bc, count1, 8, i);
296 mp_read_changes_map(mp, &bc, count2, 4, i);
299 mp->codes_count = bitstream_read(&bc, 4);
300 if (mp->codes_count == 0)
303 if (mp->changes_map[0] == 0) {
304 *(uint16_t *)mp->frame->data[0] = bitstream_read(&bc, 15);
305 mp->changes_map[0] = 1;
307 mp_read_codes_table(mp, &bc);
309 sz = bitstream_read(&bc, 18);
310 if (avctx->extradata[0] != 5)
311 sz += bitstream_read(&bc, 18);
315 if (mp->max_codes_bits <= 0)
317 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))
319 mp_decode_frame_helper(mp, &bc);
320 ff_free_vlc(&mp->vlc);
323 if ((ret = av_frame_ref(data, mp->frame)) < 0)
329 AVCodec ff_motionpixels_decoder = {
330 .name = "motionpixels",
331 .long_name = NULL_IF_CONFIG_SMALL("Motion Pixels video"),
332 .type = AVMEDIA_TYPE_VIDEO,
333 .id = AV_CODEC_ID_MOTIONPIXELS,
334 .priv_data_size = sizeof(MotionPixelsContext),
335 .init = mp_decode_init,
336 .close = mp_decode_end,
337 .decode = mp_decode_frame,
338 .capabilities = AV_CODEC_CAP_DR1,