1/*
2 * Ut Video decoder
3 * Copyright (c) 2011 Konstantin Shishkov
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 * Ut Video decoder
25 */
26
27#include <stdlib.h>
28
29#include "libavutil/intreadwrite.h"
30#include "avcodec.h"
31#include "bytestream.h"
32#include "get_bits.h"
33#include "dsputil.h"
34#include "thread.h"
35
36enum {
37    PRED_NONE = 0,
38    PRED_LEFT,
39    PRED_GRADIENT,
40    PRED_MEDIAN,
41};
42
43typedef struct UtvideoContext {
44    AVCodecContext *avctx;
45    AVFrame pic;
46    DSPContext dsp;
47
48    uint32_t frame_info_size, flags, frame_info;
49    int planes;
50    int slices;
51    int compression;
52    int interlaced;
53    int frame_pred;
54
55    uint8_t *slice_bits;
56    int slice_bits_size;
57} UtvideoContext;
58
59typedef struct HuffEntry {
60    uint8_t sym;
61    uint8_t len;
62} HuffEntry;
63
64static int huff_cmp(const void *a, const void *b)
65{
66    const HuffEntry *aa = a, *bb = b;
67    return (aa->len - bb->len)*256 + aa->sym - bb->sym;
68}
69
70static int build_huff(const uint8_t *src, VLC *vlc, int *fsym)
71{
72    int i;
73    HuffEntry he[256];
74    int last;
75    uint32_t codes[256];
76    uint8_t bits[256];
77    uint8_t syms[256];
78    uint32_t code;
79
80    *fsym = -1;
81    for (i = 0; i < 256; i++) {
82        he[i].sym = i;
83        he[i].len = *src++;
84    }
85    qsort(he, 256, sizeof(*he), huff_cmp);
86
87    if (!he[0].len) {
88        *fsym = he[0].sym;
89        return 0;
90    }
91    if (he[0].len > 32)
92        return -1;
93
94    last = 255;
95    while (he[last].len == 255 && last)
96        last--;
97
98    code = 1;
99    for (i = last; i >= 0; i--) {
100        codes[i] = code >> (32 - he[i].len);
101        bits[i]  = he[i].len;
102        syms[i]  = he[i].sym;
103        code += 0x80000000u >> (he[i].len - 1);
104    }
105
106    return ff_init_vlc_sparse(vlc, FFMIN(he[last].len, 9), last + 1,
107                              bits,  sizeof(*bits),  sizeof(*bits),
108                              codes, sizeof(*codes), sizeof(*codes),
109                              syms,  sizeof(*syms),  sizeof(*syms), 0);
110}
111
112static int decode_plane(UtvideoContext *c, int plane_no,
113                        uint8_t *dst, int step, int stride,
114                        int width, int height,
115                        const uint8_t *src, int src_size, int use_pred)
116{
117    int i, j, slice, pix;
118    int sstart, send;
119    VLC vlc;
120    GetBitContext gb;
121    int prev, fsym;
122    const int cmask = ~(!plane_no && c->avctx->pix_fmt == PIX_FMT_YUV420P);
123
124    if (build_huff(src, &vlc, &fsym)) {
125        av_log(c->avctx, AV_LOG_ERROR, "Cannot build Huffman codes\n");
126        return AVERROR_INVALIDDATA;
127    }
128    if (fsym >= 0) { // build_huff reported a symbol to fill slices with
129        send = 0;
130        for (slice = 0; slice < c->slices; slice++) {
131            uint8_t *dest;
132
133            sstart = send;
134            send   = (height * (slice + 1) / c->slices) & cmask;
135            dest   = dst + sstart * stride;
136
137            prev = 0x80;
138            for (j = sstart; j < send; j++) {
139                for (i = 0; i < width * step; i += step) {
140                    pix = fsym;
141                    if (use_pred) {
142                        prev += pix;
143                        pix   = prev;
144                    }
145                    dest[i] = pix;
146                }
147                dest += stride;
148            }
149        }
150        return 0;
151    }
152
153    src      += 256;
154    src_size -= 256;
155
156    send = 0;
157    for (slice = 0; slice < c->slices; slice++) {
158        uint8_t *dest;
159        int slice_data_start, slice_data_end, slice_size;
160
161        sstart = send;
162        send   = (height * (slice + 1) / c->slices) & cmask;
163        dest   = dst + sstart * stride;
164
165        // slice offset and size validation was done earlier
166        slice_data_start = slice ? AV_RL32(src + slice * 4 - 4) : 0;
167        slice_data_end   = AV_RL32(src + slice * 4);
168        slice_size       = slice_data_end - slice_data_start;
169
170        if (!slice_size) {
171            for (j = sstart; j < send; j++) {
172                for (i = 0; i < width * step; i += step)
173                    dest[i] = 0x80;
174                dest += stride;
175            }
176            continue;
177        }
178
179        memcpy(c->slice_bits, src + slice_data_start + c->slices * 4, slice_size);
180        memset(c->slice_bits + slice_size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
181        c->dsp.bswap_buf((uint32_t*)c->slice_bits, (uint32_t*)c->slice_bits,
182                         (slice_data_end - slice_data_start + 3) >> 2);
183        init_get_bits(&gb, c->slice_bits, slice_size * 8);
184
185        prev = 0x80;
186        for (j = sstart; j < send; j++) {
187            for (i = 0; i < width * step; i += step) {
188                if (get_bits_left(&gb) <= 0) {
189                    av_log(c->avctx, AV_LOG_ERROR, "Slice decoding ran out of bits\n");
190                    goto fail;
191                }
192                pix = get_vlc2(&gb, vlc.table, vlc.bits, 4);
193                if (pix < 0) {
194                    av_log(c->avctx, AV_LOG_ERROR, "Decoding error\n");
195                    goto fail;
196                }
197                if (use_pred) {
198                    prev += pix;
199                    pix   = prev;
200                }
201                dest[i] = pix;
202            }
203            dest += stride;
204        }
205        if (get_bits_left(&gb) > 32)
206            av_log(c->avctx, AV_LOG_WARNING, "%d bits left after decoding slice\n",
207                   get_bits_left(&gb));
208    }
209
210    ff_free_vlc(&vlc);
211
212    return 0;
213fail:
214    ff_free_vlc(&vlc);
215    return AVERROR_INVALIDDATA;
216}
217
218static const int rgb_order[4] = { 1, 2, 0, 3 };
219
220static void restore_rgb_planes(uint8_t *src, int step, int stride, int width, int height)
221{
222    int i, j;
223    uint8_t r, g, b;
224
225    for (j = 0; j < height; j++) {
226        for (i = 0; i < width * step; i += step) {
227            r = src[i];
228            g = src[i + 1];
229            b = src[i + 2];
230            src[i]     = r + g - 0x80;
231            src[i + 2] = b + g - 0x80;
232        }
233        src += stride;
234    }
235}
236
237static void restore_median(uint8_t *src, int step, int stride,
238                           int width, int height, int slices, int rmode)
239{
240    int i, j, slice;
241    int A, B, C;
242    uint8_t *bsrc;
243    int slice_start, slice_height;
244    const int cmask = ~rmode;
245
246    for (slice = 0; slice < slices; slice++) {
247        slice_start = ((slice * height) / slices) & cmask;
248        slice_height = ((((slice + 1) * height) / slices) & cmask) - slice_start;
249
250        bsrc = src + slice_start * stride;
251
252        // first line - left neighbour prediction
253        bsrc[0] += 0x80;
254        A = bsrc[0];
255        for (i = step; i < width * step; i += step) {
256            bsrc[i] += A;
257            A = bsrc[i];
258        }
259        bsrc += stride;
260        if (slice_height == 1)
261            continue;
262        // second line - first element has top predition, the rest uses median
263        C = bsrc[-stride];
264        bsrc[0] += C;
265        A = bsrc[0];
266        for (i = step; i < width * step; i += step) {
267            B = bsrc[i - stride];
268            bsrc[i] += mid_pred(A, B, (uint8_t)(A + B - C));
269            C = B;
270            A = bsrc[i];
271        }
272        bsrc += stride;
273        // the rest of lines use continuous median prediction
274        for (j = 2; j < slice_height; j++) {
275            for (i = 0; i < width * step; i += step) {
276                B = bsrc[i - stride];
277                bsrc[i] += mid_pred(A, B, (uint8_t)(A + B - C));
278                C = B;
279                A = bsrc[i];
280            }
281            bsrc += stride;
282        }
283    }
284}
285
286/* UtVideo interlaced mode treats every two lines as a single one,
287 * so restoring function should take care of possible padding between
288 * two parts of the same "line".
289 */
290static void restore_median_il(uint8_t *src, int step, int stride,
291                              int width, int height, int slices, int rmode)
292{
293    int i, j, slice;
294    int A, B, C;
295    uint8_t *bsrc;
296    int slice_start, slice_height;
297    const int cmask = ~(rmode ? 3 : 1);
298    const int stride2 = stride << 1;
299
300    for (slice = 0; slice < slices; slice++) {
301        slice_start    = ((slice * height) / slices) & cmask;
302        slice_height   = ((((slice + 1) * height) / slices) & cmask) - slice_start;
303        slice_height >>= 1;
304
305        bsrc = src + slice_start * stride;
306
307        // first line - left neighbour prediction
308        bsrc[0] += 0x80;
309        A = bsrc[0];
310        for (i = step; i < width * step; i += step) {
311            bsrc[i] += A;
312            A = bsrc[i];
313        }
314        for (i = 0; i < width * step; i += step) {
315            bsrc[stride + i] += A;
316            A = bsrc[stride + i];
317        }
318        bsrc += stride2;
319        if (slice_height == 1)
320            continue;
321        // second line - first element has top predition, the rest uses median
322        C = bsrc[-stride2];
323        bsrc[0] += C;
324        A = bsrc[0];
325        for (i = step; i < width * step; i += step) {
326            B = bsrc[i - stride2];
327            bsrc[i] += mid_pred(A, B, (uint8_t)(A + B - C));
328            C = B;
329            A = bsrc[i];
330        }
331        for (i = 0; i < width * step; i += step) {
332            B = bsrc[i - stride];
333            bsrc[stride + i] += mid_pred(A, B, (uint8_t)(A + B - C));
334            C = B;
335            A = bsrc[stride + i];
336        }
337        bsrc += stride2;
338        // the rest of lines use continuous median prediction
339        for (j = 2; j < slice_height; j++) {
340            for (i = 0; i < width * step; i += step) {
341                B = bsrc[i - stride2];
342                bsrc[i] += mid_pred(A, B, (uint8_t)(A + B - C));
343                C = B;
344                A = bsrc[i];
345            }
346            for (i = 0; i < width * step; i += step) {
347                B = bsrc[i - stride];
348                bsrc[i + stride] += mid_pred(A, B, (uint8_t)(A + B - C));
349                C = B;
350                A = bsrc[i + stride];
351            }
352            bsrc += stride2;
353        }
354    }
355}
356
357static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt)
358{
359    const uint8_t *buf = avpkt->data;
360    int buf_size = avpkt->size;
361    UtvideoContext *c = avctx->priv_data;
362    int i, j;
363    const uint8_t *plane_start[5];
364    int plane_size, max_slice_size = 0, slice_start, slice_end, slice_size;
365    int ret;
366    GetByteContext gb;
367
368    if (c->pic.data[0])
369        ff_thread_release_buffer(avctx, &c->pic);
370
371    c->pic.reference = 1;
372    c->pic.buffer_hints = FF_BUFFER_HINTS_VALID;
373    if ((ret = ff_thread_get_buffer(avctx, &c->pic)) < 0) {
374        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
375        return ret;
376    }
377
378    ff_thread_finish_setup(avctx);
379
380    /* parse plane structure to retrieve frame flags and validate slice offsets */
381    bytestream2_init(&gb, buf, buf_size);
382    for (i = 0; i < c->planes; i++) {
383        plane_start[i] = gb.buffer;
384        if (bytestream2_get_bytes_left(&gb) < 256 + 4 * c->slices) {
385            av_log(avctx, AV_LOG_ERROR, "Insufficient data for a plane\n");
386            return AVERROR_INVALIDDATA;
387        }
388        bytestream2_skipu(&gb, 256);
389        slice_start = 0;
390        slice_end   = 0;
391        for (j = 0; j < c->slices; j++) {
392            slice_end   = bytestream2_get_le32u(&gb);
393            slice_size  = slice_end - slice_start;
394            if (slice_end <= 0 || slice_size <= 0 ||
395                bytestream2_get_bytes_left(&gb) < slice_end) {
396                av_log(avctx, AV_LOG_ERROR, "Incorrect slice size\n");
397                return AVERROR_INVALIDDATA;
398            }
399            slice_start = slice_end;
400            max_slice_size = FFMAX(max_slice_size, slice_size);
401        }
402        plane_size = slice_end;
403        bytestream2_skipu(&gb, plane_size);
404    }
405    plane_start[c->planes] = gb.buffer;
406    if (bytestream2_get_bytes_left(&gb) < c->frame_info_size) {
407        av_log(avctx, AV_LOG_ERROR, "Not enough data for frame information\n");
408        return AVERROR_INVALIDDATA;
409    }
410    c->frame_info = bytestream2_get_le32u(&gb);
411    av_log(avctx, AV_LOG_DEBUG, "frame information flags %X\n", c->frame_info);
412
413    c->frame_pred = (c->frame_info >> 8) & 3;
414
415    if (c->frame_pred == PRED_GRADIENT) {
416        av_log_ask_for_sample(avctx, "Frame uses gradient prediction\n");
417        return AVERROR_PATCHWELCOME;
418    }
419
420    av_fast_malloc(&c->slice_bits, &c->slice_bits_size,
421                   max_slice_size + FF_INPUT_BUFFER_PADDING_SIZE);
422
423    if (!c->slice_bits) {
424        av_log(avctx, AV_LOG_ERROR, "Cannot allocate temporary buffer\n");
425        return AVERROR(ENOMEM);
426    }
427
428    switch (c->avctx->pix_fmt) {
429    case PIX_FMT_RGB24:
430    case PIX_FMT_RGBA:
431        for (i = 0; i < c->planes; i++) {
432            ret = decode_plane(c, i, c->pic.data[0] + rgb_order[i], c->planes,
433                               c->pic.linesize[0], avctx->width, avctx->height,
434                               plane_start[i], plane_start[i + 1] - plane_start[i],
435                               c->frame_pred == PRED_LEFT);
436            if (ret)
437                return ret;
438            if (c->frame_pred == PRED_MEDIAN)
439                restore_median(c->pic.data[0] + rgb_order[i], c->planes,
440                               c->pic.linesize[0], avctx->width, avctx->height,
441                               c->slices, 0);
442        }
443        restore_rgb_planes(c->pic.data[0], c->planes, c->pic.linesize[0],
444                           avctx->width, avctx->height);
445        break;
446    case PIX_FMT_YUV420P:
447        for (i = 0; i < 3; i++) {
448            ret = decode_plane(c, i, c->pic.data[i], 1,
449                               c->pic.linesize[i], avctx->width >> !!i, avctx->height >> !!i,
450                               plane_start[i], plane_start[i + 1] - plane_start[i],
451                               c->frame_pred == PRED_LEFT);
452            if (ret)
453                return ret;
454            if (c->frame_pred == PRED_MEDIAN) {
455                if (!c->interlaced) {
456                    restore_median(c->pic.data[i], 1, c->pic.linesize[i],
457                                   avctx->width >> !!i, avctx->height >> !!i,
458                                   c->slices, !i);
459                } else {
460                    restore_median_il(c->pic.data[i], 1, c->pic.linesize[i],
461                                      avctx->width  >> !!i,
462                                      avctx->height >> !!i,
463                                      c->slices, !i);
464                }
465            }
466        }
467        break;
468    case PIX_FMT_YUV422P:
469        for (i = 0; i < 3; i++) {
470            ret = decode_plane(c, i, c->pic.data[i], 1,
471                               c->pic.linesize[i], avctx->width >> !!i, avctx->height,
472                               plane_start[i], plane_start[i + 1] - plane_start[i],
473                               c->frame_pred == PRED_LEFT);
474            if (ret)
475                return ret;
476            if (c->frame_pred == PRED_MEDIAN) {
477                if (!c->interlaced) {
478                    restore_median(c->pic.data[i], 1, c->pic.linesize[i],
479                                   avctx->width >> !!i, avctx->height,
480                                   c->slices, 0);
481                } else {
482                    restore_median_il(c->pic.data[i], 1, c->pic.linesize[i],
483                                      avctx->width >> !!i, avctx->height,
484                                      c->slices, 0);
485                }
486            }
487        }
488        break;
489    }
490
491    *data_size = sizeof(AVFrame);
492    *(AVFrame*)data = c->pic;
493
494    /* always report that the buffer was completely consumed */
495    return buf_size;
496}
497
498static av_cold int decode_init(AVCodecContext *avctx)
499{
500    UtvideoContext * const c = avctx->priv_data;
501
502    c->avctx = avctx;
503
504    dsputil_init(&c->dsp, avctx);
505
506    if (avctx->extradata_size < 16) {
507        av_log(avctx, AV_LOG_ERROR, "Insufficient extradata size %d, should be at least 16\n",
508               avctx->extradata_size);
509        return AVERROR_INVALIDDATA;
510    }
511
512    av_log(avctx, AV_LOG_DEBUG, "Encoder version %d.%d.%d.%d\n",
513           avctx->extradata[3], avctx->extradata[2],
514           avctx->extradata[1], avctx->extradata[0]);
515    av_log(avctx, AV_LOG_DEBUG, "Original format %X\n", AV_RB32(avctx->extradata + 4));
516    c->frame_info_size = AV_RL32(avctx->extradata + 8);
517    c->flags           = AV_RL32(avctx->extradata + 12);
518
519    if (c->frame_info_size != 4)
520        av_log_ask_for_sample(avctx, "Frame info is not 4 bytes\n");
521    av_log(avctx, AV_LOG_DEBUG, "Encoding parameters %08X\n", c->flags);
522    c->slices      = (c->flags >> 24) + 1;
523    c->compression = c->flags & 1;
524    c->interlaced  = c->flags & 0x800;
525
526    c->slice_bits_size = 0;
527
528    switch (avctx->codec_tag) {
529    case MKTAG('U', 'L', 'R', 'G'):
530        c->planes      = 3;
531        avctx->pix_fmt = PIX_FMT_RGB24;
532        break;
533    case MKTAG('U', 'L', 'R', 'A'):
534        c->planes      = 4;
535        avctx->pix_fmt = PIX_FMT_RGBA;
536        break;
537    case MKTAG('U', 'L', 'Y', '0'):
538        c->planes      = 3;
539        avctx->pix_fmt = PIX_FMT_YUV420P;
540        break;
541    case MKTAG('U', 'L', 'Y', '2'):
542        c->planes      = 3;
543        avctx->pix_fmt = PIX_FMT_YUV422P;
544        break;
545    default:
546        av_log(avctx, AV_LOG_ERROR, "Unknown Ut Video FOURCC provided (%08X)\n",
547               avctx->codec_tag);
548        return AVERROR_INVALIDDATA;
549    }
550
551    return 0;
552}
553
554static av_cold int decode_end(AVCodecContext *avctx)
555{
556    UtvideoContext * const c = avctx->priv_data;
557
558    if (c->pic.data[0])
559        ff_thread_release_buffer(avctx, &c->pic);
560
561    av_freep(&c->slice_bits);
562
563    return 0;
564}
565
566AVCodec ff_utvideo_decoder = {
567    .name           = "utvideo",
568    .type           = AVMEDIA_TYPE_VIDEO,
569    .id             = CODEC_ID_UTVIDEO,
570    .priv_data_size = sizeof(UtvideoContext),
571    .init           = decode_init,
572    .close          = decode_end,
573    .decode         = decode_frame,
574    .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS,
575    .long_name      = NULL_IF_CONFIG_SMALL("Ut Video"),
576};
577
578