xref: /third_party/ffmpeg/libavcodec/pixlet.c (revision cabdff1a)
1/*
2 * Apple Pixlet decoder
3 * Copyright (c) 2016 Paul B Mahol
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg 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 * FFmpeg 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 FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22#include <stdint.h>
23
24#include "libavutil/imgutils.h"
25#include "libavutil/intmath.h"
26#include "libavutil/opt.h"
27
28#include "avcodec.h"
29#include "bytestream.h"
30#include "codec_internal.h"
31#include "get_bits.h"
32#include "internal.h"
33#include "thread.h"
34#include "unary.h"
35
36#define NB_LEVELS 4
37
38#define PIXLET_MAGIC 0xDEADBEEF
39
40#define H 0
41#define V 1
42
43typedef struct SubBand {
44    unsigned width, height;
45    unsigned size;
46    unsigned x, y;
47} SubBand;
48
49typedef struct PixletContext {
50    AVClass *class;
51
52    GetByteContext gb;
53    GetBitContext bc;
54
55    int levels;
56    int depth;
57    int w, h;
58
59    int16_t *filter[2];
60    int16_t *prediction;
61    int64_t scaling[4][2][NB_LEVELS];
62    uint16_t lut[65536];
63    SubBand band[4][NB_LEVELS * 3 + 1];
64} PixletContext;
65
66static av_cold int pixlet_init(AVCodecContext *avctx)
67{
68    avctx->pix_fmt     = AV_PIX_FMT_YUV420P16;
69    avctx->color_range = AVCOL_RANGE_JPEG;
70    return 0;
71}
72
73static void free_buffers(AVCodecContext *avctx)
74{
75    PixletContext *ctx = avctx->priv_data;
76
77    av_freep(&ctx->filter[0]);
78    av_freep(&ctx->filter[1]);
79    av_freep(&ctx->prediction);
80}
81
82static av_cold int pixlet_close(AVCodecContext *avctx)
83{
84    PixletContext *ctx = avctx->priv_data;
85    free_buffers(avctx);
86    ctx->w = 0;
87    ctx->h = 0;
88    return 0;
89}
90
91static int init_decoder(AVCodecContext *avctx)
92{
93    PixletContext *ctx = avctx->priv_data;
94    int i, plane;
95
96    ctx->filter[0]  = av_malloc_array(ctx->h, sizeof(int16_t));
97    ctx->filter[1]  = av_malloc_array(FFMAX(ctx->h, ctx->w) + 16, sizeof(int16_t));
98    ctx->prediction = av_malloc_array((ctx->w >> NB_LEVELS), sizeof(int16_t));
99    if (!ctx->filter[0] || !ctx->filter[1] || !ctx->prediction)
100        return AVERROR(ENOMEM);
101
102    for (plane = 0; plane < 3; plane++) {
103        unsigned shift = plane > 0;
104        unsigned w     = ctx->w >> shift;
105        unsigned h     = ctx->h >> shift;
106
107        ctx->band[plane][0].width  =  w >> NB_LEVELS;
108        ctx->band[plane][0].height =  h >> NB_LEVELS;
109        ctx->band[plane][0].size   = (w >> NB_LEVELS) * (h >> NB_LEVELS);
110
111        for (i = 0; i < NB_LEVELS * 3; i++) {
112            unsigned scale = ctx->levels - (i / 3);
113
114            ctx->band[plane][i + 1].width  =  w >> scale;
115            ctx->band[plane][i + 1].height =  h >> scale;
116            ctx->band[plane][i + 1].size   = (w >> scale) * (h >> scale);
117
118            ctx->band[plane][i + 1].x = (w >> scale) * (((i + 1) % 3) != 2);
119            ctx->band[plane][i + 1].y = (h >> scale) * (((i + 1) % 3) != 1);
120        }
121    }
122
123    return 0;
124}
125
126static int read_low_coeffs(AVCodecContext *avctx, int16_t *dst, int size,
127                           int width, ptrdiff_t stride)
128{
129    PixletContext *ctx = avctx->priv_data;
130    GetBitContext *bc = &ctx->bc;
131    unsigned cnt1, nbits, k, j = 0, i = 0;
132    int64_t value, state = 3;
133    int rlen, escape, flag = 0;
134
135    while (i < size) {
136        nbits = FFMIN(ff_clz((state >> 8) + 3) ^ 0x1F, 14);
137
138        cnt1 = get_unary(bc, 0, 8);
139        if (cnt1 < 8) {
140            value = show_bits(bc, nbits);
141            if (value <= 1) {
142                skip_bits(bc, nbits - 1);
143                escape = ((1 << nbits) - 1) * cnt1;
144            } else {
145                skip_bits(bc, nbits);
146                escape = value + ((1 << nbits) - 1) * cnt1 - 1;
147            }
148        } else {
149            escape = get_bits(bc, 16);
150        }
151
152        value    = -((escape + flag) & 1) | 1;
153        dst[j++] = value * ((escape + flag + 1) >> 1);
154        i++;
155        if (j == width) {
156            j    = 0;
157            dst += stride;
158        }
159        state = 120 * (escape + flag) + state - (120 * state >> 8);
160        flag  = 0;
161
162        if (state * 4ULL > 0xFF || i >= size)
163            continue;
164
165        nbits  = ((state + 8) >> 5) + (state ? ff_clz(state) : 32) - 24;
166        escape = av_mod_uintp2(16383, nbits);
167        cnt1   = get_unary(bc, 0, 8);
168        if (cnt1 > 7) {
169            rlen = get_bits(bc, 16);
170        } else {
171            value = show_bits(bc, nbits);
172            if (value > 1) {
173                skip_bits(bc, nbits);
174                rlen = value + escape * cnt1 - 1;
175            } else {
176                skip_bits(bc, nbits - 1);
177                rlen = escape * cnt1;
178            }
179        }
180
181        if (rlen > size - i)
182            return AVERROR_INVALIDDATA;
183        i += rlen;
184
185        for (k = 0; k < rlen; k++) {
186            dst[j++] = 0;
187            if (j == width) {
188                j    = 0;
189                dst += stride;
190            }
191        }
192
193        state = 0;
194        flag  = rlen < 0xFFFF ? 1 : 0;
195    }
196
197    align_get_bits(bc);
198    return get_bits_count(bc) >> 3;
199}
200
201static int read_high_coeffs(AVCodecContext *avctx, const uint8_t *src, int16_t *dst,
202                            int size, int c, int a, int d,
203                            int width, ptrdiff_t stride)
204{
205    PixletContext *ctx = avctx->priv_data;
206    GetBitContext *bc = &ctx->bc;
207    unsigned cnt1, shbits, rlen, nbits, length, i = 0, j = 0, k;
208    int ret, escape, pfx, value, yflag, xflag, flag = 0;
209    int64_t state = 3, tmp;
210
211    ret = init_get_bits8(bc, src, bytestream2_get_bytes_left(&ctx->gb));
212    if (ret < 0)
213        return ret;
214
215    if (a ^ (a >> 31)) {
216        nbits = 33 - ff_clz(a ^ (a >> 31));
217        if (nbits > 16)
218            return AVERROR_INVALIDDATA;
219    } else {
220        nbits = 1;
221    }
222
223    length = 25 - nbits;
224
225    while (i < size) {
226        if (((state >> 8) + 3) & 0xFFFFFFF)
227            value = ff_clz((state >> 8) + 3) ^ 0x1F;
228        else
229            value = -1;
230
231        cnt1 = get_unary(bc, 0, length);
232        if (cnt1 >= length) {
233            cnt1 = get_bits(bc, nbits);
234        } else {
235            pfx = 14 + ((((uint64_t)(value - 14)) >> 32) & (value - 14));
236            if (pfx < 1 || pfx > 25)
237                return AVERROR_INVALIDDATA;
238            cnt1 *= (1 << pfx) - 1;
239            shbits = show_bits(bc, pfx);
240            if (shbits <= 1) {
241                skip_bits(bc, pfx - 1);
242            } else {
243                skip_bits(bc, pfx);
244                cnt1 += shbits - 1;
245            }
246        }
247
248        xflag = flag + cnt1;
249        yflag = xflag;
250
251        if (flag + cnt1 == 0) {
252            value = 0;
253        } else {
254            xflag &= 1u;
255            tmp    = (int64_t)c * ((yflag + 1) >> 1) + (c >> 1);
256            value  = xflag + (tmp ^ -xflag);
257        }
258
259        i++;
260        dst[j++] = value;
261        if (j == width) {
262            j    = 0;
263            dst += stride;
264        }
265        state += (int64_t)d * (uint64_t)yflag - ((int64_t)(d * (uint64_t)state) >> 8);
266
267        flag = 0;
268
269        if ((uint64_t)state > 0xFF / 4 || i >= size)
270            continue;
271
272        pfx    = ((state + 8) >> 5) + (state ? ff_clz(state) : 32) - 24;
273        escape = av_mod_uintp2(16383, pfx);
274        cnt1   = get_unary(bc, 0, 8);
275        if (cnt1 < 8) {
276            if (pfx < 1 || pfx > 25)
277                return AVERROR_INVALIDDATA;
278
279            value = show_bits(bc, pfx);
280            if (value > 1) {
281                skip_bits(bc, pfx);
282                rlen = value + escape * cnt1 - 1;
283            } else {
284                skip_bits(bc, pfx - 1);
285                rlen = escape * cnt1;
286            }
287        } else {
288            if (get_bits1(bc))
289                value = get_bits(bc, 16);
290            else
291                value = get_bits(bc, 8);
292
293            rlen = value + 8 * escape;
294        }
295
296        if (rlen > 0xFFFF || i + rlen > size)
297            return AVERROR_INVALIDDATA;
298        i += rlen;
299
300        for (k = 0; k < rlen; k++) {
301            dst[j++] = 0;
302            if (j == width) {
303                j    = 0;
304                dst += stride;
305            }
306        }
307
308        state = 0;
309        flag  = rlen < 0xFFFF ? 1 : 0;
310    }
311
312    align_get_bits(bc);
313    return get_bits_count(bc) >> 3;
314}
315
316static int read_highpass(AVCodecContext *avctx, const uint8_t *ptr,
317                         int plane, AVFrame *frame)
318{
319    PixletContext *ctx = avctx->priv_data;
320    ptrdiff_t stride = frame->linesize[plane] / 2;
321    int i, ret;
322
323    for (i = 0; i < ctx->levels * 3; i++) {
324        int32_t a = bytestream2_get_be32(&ctx->gb);
325        int32_t b = bytestream2_get_be32(&ctx->gb);
326        int32_t c = bytestream2_get_be32(&ctx->gb);
327        int32_t d = bytestream2_get_be32(&ctx->gb);
328        int16_t *dest = (int16_t *)frame->data[plane] +
329                        ctx->band[plane][i + 1].x +
330                        ctx->band[plane][i + 1].y * stride;
331        unsigned size = ctx->band[plane][i + 1].size;
332        uint32_t magic = bytestream2_get_be32(&ctx->gb);
333
334        if (magic != PIXLET_MAGIC) {
335            av_log(avctx, AV_LOG_ERROR,
336                   "wrong magic number: 0x%08"PRIX32" for plane %d, band %d\n",
337                   magic, plane, i);
338            return AVERROR_INVALIDDATA;
339        }
340
341        if (a == INT32_MIN)
342            return AVERROR_INVALIDDATA;
343
344        ret = read_high_coeffs(avctx, ptr + bytestream2_tell(&ctx->gb), dest, size,
345                               c, (b >= FFABS(a)) ? b : a, d,
346                               ctx->band[plane][i + 1].width, stride);
347        if (ret < 0) {
348            av_log(avctx, AV_LOG_ERROR,
349                   "error in highpass coefficients for plane %d, band %d\n",
350                   plane, i);
351            return ret;
352        }
353        bytestream2_skip(&ctx->gb, ret);
354    }
355
356    return 0;
357}
358
359static void lowpass_prediction(int16_t *dst, int16_t *pred,
360                               int width, int height, ptrdiff_t stride)
361{
362    int16_t val;
363    int i, j;
364
365    memset(pred, 0, width * sizeof(*pred));
366
367    for (i = 0; i < height; i++) {
368        val    = pred[0] + dst[0];
369        dst[0] = pred[0] = val;
370        for (j = 1; j < width; j++) {
371            val     = pred[j] + dst[j];
372            dst[j]  = pred[j] = val;
373            dst[j] += dst[j-1];
374        }
375        dst += stride;
376    }
377}
378
379static void filterfn(int16_t *dest, int16_t *tmp, unsigned size, int64_t scale)
380{
381    int16_t *low, *high, *ll, *lh, *hl, *hh;
382    int hsize, i, j;
383    int64_t value;
384
385    hsize = size >> 1;
386    low   = tmp + 4;
387    high  = &low[hsize + 8];
388
389    memcpy(low, dest, size);
390    memcpy(high, dest + hsize, size);
391
392    ll = &low[hsize];
393    lh = &low[hsize];
394    hl = &high[hsize];
395    hh = hl;
396    for (i = 4, j = 2; i; i--, j++, ll--, hh++, lh++, hl--) {
397        low[i - 5]  = low[j - 1];
398        lh[0]       = ll[-1];
399        high[i - 5] = high[j - 2];
400        hh[0]       = hl[-2];
401    }
402
403    for (i = 0; i < hsize; i++) {
404        value = (int64_t) low [i + 1] * -INT64_C(325392907)  +
405                (int64_t) low [i + 0] *  INT64_C(3687786320) +
406                (int64_t) low [i - 1] * -INT64_C(325392907)  +
407                (int64_t) high[i + 0] *  INT64_C(1518500249) +
408                (int64_t) high[i - 1] *  INT64_C(1518500249);
409        dest[i * 2] = av_clip_int16(((value >> 32) * (uint64_t)scale) >> 32);
410    }
411
412    for (i = 0; i < hsize; i++) {
413        value = (int64_t) low [i + 2] * -INT64_C(65078576)   +
414                (int64_t) low [i + 1] *  INT64_C(1583578880) +
415                (int64_t) low [i + 0] *  INT64_C(1583578880) +
416                (int64_t) low [i - 1] * -INT64_C(65078576)   +
417                (int64_t) high[i + 1] *  INT64_C(303700064)  +
418                (int64_t) high[i + 0] * -INT64_C(3644400640) +
419                (int64_t) high[i - 1] *  INT64_C(303700064);
420        dest[i * 2 + 1] = av_clip_int16(((value >> 32) * (uint64_t)scale) >> 32);
421    }
422}
423
424static void reconstruction(AVCodecContext *avctx, int16_t *dest,
425                           unsigned width, unsigned height, ptrdiff_t stride,
426                           int64_t *scaling_h, int64_t *scaling_v)
427{
428    PixletContext *ctx = avctx->priv_data;
429    unsigned scaled_width, scaled_height;
430    int16_t *ptr, *tmp;
431    int i, j, k;
432
433    scaled_width  = width  >> NB_LEVELS;
434    scaled_height = height >> NB_LEVELS;
435    tmp           = ctx->filter[0];
436
437    for (i = 0; i < NB_LEVELS; i++) {
438        int64_t scale_v = scaling_v[i];
439        int64_t scale_h = scaling_h[i];
440        scaled_width  <<= 1;
441        scaled_height <<= 1;
442
443        ptr = dest;
444        for (j = 0; j < scaled_height; j++) {
445            filterfn(ptr, ctx->filter[1], scaled_width, scale_v);
446            ptr += stride;
447        }
448
449        for (j = 0; j < scaled_width; j++) {
450            ptr = dest + j;
451            for (k = 0; k < scaled_height; k++) {
452                tmp[k] = *ptr;
453                ptr   += stride;
454            }
455
456            filterfn(tmp, ctx->filter[1], scaled_height, scale_h);
457
458            ptr = dest + j;
459            for (k = 0; k < scaled_height; k++) {
460                *ptr = tmp[k];
461                ptr += stride;
462            }
463        }
464    }
465}
466
467static void build_luma_lut(AVCodecContext *avctx, int depth)
468{
469    PixletContext *ctx = avctx->priv_data;
470    int max = (1 << depth) - 1;
471
472    if (ctx->depth == depth)
473        return;
474    ctx->depth = depth;
475
476    for (int i = 0; i < FF_ARRAY_ELEMS(ctx->lut); i++)
477        ctx->lut[i] = ((int64_t)i * i * 65535LL) / max / max;
478}
479
480static void postprocess_luma(AVCodecContext *avctx, AVFrame *frame,
481                             int w, int h, int depth)
482{
483    PixletContext *ctx = avctx->priv_data;
484    uint16_t *dsty = (uint16_t *)frame->data[0];
485    int16_t *srcy  = (int16_t *)frame->data[0];
486    ptrdiff_t stridey = frame->linesize[0] / 2;
487    uint16_t *lut = ctx->lut;
488    int i, j;
489
490    for (j = 0; j < h; j++) {
491        for (i = 0; i < w; i++) {
492            if (srcy[i] <= 0)
493                dsty[i] = 0;
494            else if (srcy[i] > ((1 << depth) - 1))
495                dsty[i] = 65535;
496            else
497                dsty[i] = lut[srcy[i]];
498        }
499        dsty += stridey;
500        srcy += stridey;
501    }
502}
503
504static void postprocess_chroma(AVFrame *frame, int w, int h, int depth)
505{
506    uint16_t *dstu = (uint16_t *)frame->data[1];
507    uint16_t *dstv = (uint16_t *)frame->data[2];
508    int16_t *srcu  = (int16_t *)frame->data[1];
509    int16_t *srcv  = (int16_t *)frame->data[2];
510    ptrdiff_t strideu = frame->linesize[1] / 2;
511    ptrdiff_t stridev = frame->linesize[2] / 2;
512    const unsigned add = 1 << (depth - 1);
513    const unsigned shift = 16 - depth;
514    int i, j;
515
516    for (j = 0; j < h; j++) {
517        for (i = 0; i < w; i++) {
518            dstu[i] = av_clip_uintp2_c(add + srcu[i], depth) << shift;
519            dstv[i] = av_clip_uintp2_c(add + srcv[i], depth) << shift;
520        }
521        dstu += strideu;
522        dstv += stridev;
523        srcu += strideu;
524        srcv += stridev;
525    }
526}
527
528static int decode_plane(AVCodecContext *avctx, int plane,
529                        const AVPacket *avpkt, AVFrame *frame)
530{
531    PixletContext *ctx = avctx->priv_data;
532    ptrdiff_t stride   = frame->linesize[plane] / 2;
533    unsigned shift     = plane > 0;
534    int16_t *dst;
535    int i, ret;
536
537    for (i = ctx->levels - 1; i >= 0; i--) {
538        int32_t h = sign_extend(bytestream2_get_be32(&ctx->gb), 32);
539        int32_t v = sign_extend(bytestream2_get_be32(&ctx->gb), 32);
540
541        if (!h || !v)
542            return AVERROR_INVALIDDATA;
543
544        ctx->scaling[plane][H][i] = (1000000ULL << 32) / h;
545        ctx->scaling[plane][V][i] = (1000000ULL << 32) / v;
546    }
547
548    bytestream2_skip(&ctx->gb, 4);
549
550    dst    = (int16_t *)frame->data[plane];
551    dst[0] = sign_extend(bytestream2_get_be16(&ctx->gb), 16);
552
553    ret = init_get_bits8(&ctx->bc, avpkt->data + bytestream2_tell(&ctx->gb),
554                         bytestream2_get_bytes_left(&ctx->gb));
555    if (ret < 0)
556        return ret;
557
558    ret = read_low_coeffs(avctx, dst + 1, ctx->band[plane][0].width - 1,
559                          ctx->band[plane][0].width - 1, 0);
560    if (ret < 0) {
561        av_log(avctx, AV_LOG_ERROR,
562               "error in lowpass coefficients for plane %d, top row\n", plane);
563        return ret;
564    }
565
566    ret = read_low_coeffs(avctx, dst + stride,
567                          ctx->band[plane][0].height - 1, 1, stride);
568    if (ret < 0) {
569        av_log(avctx, AV_LOG_ERROR,
570               "error in lowpass coefficients for plane %d, left column\n",
571               plane);
572        return ret;
573    }
574
575    ret = read_low_coeffs(avctx, dst + stride + 1,
576                          (ctx->band[plane][0].width - 1) * (ctx->band[plane][0].height - 1),
577                          ctx->band[plane][0].width - 1, stride);
578    if (ret < 0) {
579        av_log(avctx, AV_LOG_ERROR,
580               "error in lowpass coefficients for plane %d, rest\n", plane);
581        return ret;
582    }
583
584    bytestream2_skip(&ctx->gb, ret);
585    if (bytestream2_get_bytes_left(&ctx->gb) <= 0) {
586        av_log(avctx, AV_LOG_ERROR, "no bytes left\n");
587        return AVERROR_INVALIDDATA;
588    }
589
590    ret = read_highpass(avctx, avpkt->data, plane, frame);
591    if (ret < 0)
592        return ret;
593
594    lowpass_prediction(dst, ctx->prediction, ctx->band[plane][0].width,
595                       ctx->band[plane][0].height, stride);
596
597    reconstruction(avctx, (int16_t *)frame->data[plane], ctx->w >> shift,
598                   ctx->h >> shift, stride, ctx->scaling[plane][H],
599                   ctx->scaling[plane][V]);
600
601    return 0;
602}
603
604static int pixlet_decode_frame(AVCodecContext *avctx, AVFrame *p,
605                               int *got_frame, AVPacket *avpkt)
606{
607    PixletContext *ctx = avctx->priv_data;
608    int i, w, h, width, height, ret, version;
609    uint32_t pktsize, depth;
610
611    bytestream2_init(&ctx->gb, avpkt->data, avpkt->size);
612
613    pktsize = bytestream2_get_be32(&ctx->gb);
614    if (pktsize <= 44 + (NB_LEVELS * 8 + 6) * 3 || pktsize - 4 > bytestream2_get_bytes_left(&ctx->gb)) {
615        av_log(avctx, AV_LOG_ERROR, "Invalid packet size %"PRIu32"\n", pktsize);
616        return AVERROR_INVALIDDATA;
617    }
618
619    version = bytestream2_get_le32(&ctx->gb);
620    if (version != 1)
621        avpriv_request_sample(avctx, "Version %d", version);
622
623    bytestream2_skip(&ctx->gb, 4);
624    if (bytestream2_get_be32(&ctx->gb) != 1)
625        return AVERROR_INVALIDDATA;
626    bytestream2_skip(&ctx->gb, 4);
627
628    width  = bytestream2_get_be32(&ctx->gb);
629    height = bytestream2_get_be32(&ctx->gb);
630
631    if (    width > INT_MAX - (1U << (NB_LEVELS + 1))
632        || height > INT_MAX - (1U << (NB_LEVELS + 1)))
633        return AVERROR_INVALIDDATA;
634
635    w = FFALIGN(width,  1 << (NB_LEVELS + 1));
636    h = FFALIGN(height, 1 << (NB_LEVELS + 1));
637
638    ctx->levels = bytestream2_get_be32(&ctx->gb);
639    if (ctx->levels != NB_LEVELS)
640        return AVERROR_INVALIDDATA;
641    depth = bytestream2_get_be32(&ctx->gb);
642    if (depth < 8 || depth > 15) {
643        avpriv_request_sample(avctx, "Depth %d", depth);
644        return AVERROR_INVALIDDATA;
645    }
646
647    build_luma_lut(avctx, depth);
648
649    ret = ff_set_dimensions(avctx, w, h);
650    if (ret < 0)
651        return ret;
652    avctx->width  = width;
653    avctx->height = height;
654
655    if (ctx->w != w || ctx->h != h) {
656        free_buffers(avctx);
657        ctx->w = w;
658        ctx->h = h;
659
660        ret = init_decoder(avctx);
661        if (ret < 0) {
662            free_buffers(avctx);
663            ctx->w = 0;
664            ctx->h = 0;
665            return ret;
666        }
667    }
668
669    bytestream2_skip(&ctx->gb, 8);
670
671    p->pict_type = AV_PICTURE_TYPE_I;
672    p->key_frame = 1;
673    p->color_range = AVCOL_RANGE_JPEG;
674
675    ret = ff_thread_get_buffer(avctx, p, 0);
676    if (ret < 0)
677        return ret;
678
679    for (i = 0; i < 3; i++) {
680        ret = decode_plane(avctx, i, avpkt, p);
681        if (ret < 0)
682            return ret;
683        if (avctx->flags & AV_CODEC_FLAG_GRAY)
684            break;
685    }
686
687    postprocess_luma(avctx, p, ctx->w, ctx->h, ctx->depth);
688    postprocess_chroma(p, ctx->w >> 1, ctx->h >> 1, ctx->depth);
689
690    *got_frame = 1;
691
692    return pktsize;
693}
694
695const FFCodec ff_pixlet_decoder = {
696    .p.name           = "pixlet",
697    .p.long_name      = NULL_IF_CONFIG_SMALL("Apple Pixlet"),
698    .p.type           = AVMEDIA_TYPE_VIDEO,
699    .p.id             = AV_CODEC_ID_PIXLET,
700    .init             = pixlet_init,
701    .close            = pixlet_close,
702    FF_CODEC_DECODE_CB(pixlet_decode_frame),
703    .priv_data_size   = sizeof(PixletContext),
704    .p.capabilities   = AV_CODEC_CAP_DR1 |
705                        AV_CODEC_CAP_FRAME_THREADS,
706    .caps_internal    = FF_CODEC_CAP_INIT_THREADSAFE |
707                        FF_CODEC_CAP_INIT_CLEANUP,
708};
709