PageRenderTime 48ms CodeModel.GetById 9ms app.highlight 34ms RepoModel.GetById 1ms app.codeStats 0ms

/libavcodec/cljr.c

http://github.com/FFmpeg/FFmpeg
C | 211 lines | 158 code | 29 blank | 24 comment | 12 complexity | 1299cbfefa04c7d55c451cccf27038ff MD5 | raw file
  1/*
  2 * Cirrus Logic AccuPak (CLJR) codec
  3 * Copyright (c) 2003 Alex Beregszaszi
  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/**
 23 * @file
 24 * Cirrus Logic AccuPak codec.
 25 */
 26
 27#include "avcodec.h"
 28#include "libavutil/opt.h"
 29#include "get_bits.h"
 30#include "internal.h"
 31#include "put_bits.h"
 32
 33typedef struct CLJRContext {
 34    AVClass        *avclass;
 35    AVFrame         picture;
 36    int             dither_type;
 37} CLJRContext;
 38
 39static av_cold int common_init(AVCodecContext *avctx)
 40{
 41    CLJRContext * const a = avctx->priv_data;
 42
 43    avcodec_get_frame_defaults(&a->picture);
 44    avctx->coded_frame = &a->picture;
 45
 46    return 0;
 47}
 48
 49#if CONFIG_CLJR_DECODER
 50static int decode_frame(AVCodecContext *avctx,
 51                        void *data, int *data_size,
 52                        AVPacket *avpkt)
 53{
 54    const uint8_t *buf = avpkt->data;
 55    int buf_size       = avpkt->size;
 56    CLJRContext * const a = avctx->priv_data;
 57    GetBitContext gb;
 58    AVFrame *picture = data;
 59    AVFrame * const p = &a->picture;
 60    int x, y, ret;
 61
 62    if (p->data[0])
 63        avctx->release_buffer(avctx, p);
 64
 65    if (avctx->height <= 0 || avctx->width <= 0) {
 66        av_log(avctx, AV_LOG_ERROR, "Invalid width or height\n");
 67        return AVERROR_INVALIDDATA;
 68    }
 69
 70    if (buf_size / avctx->height < avctx->width) {
 71        av_log(avctx, AV_LOG_ERROR,
 72               "Resolution larger than buffer size. Invalid header?\n");
 73        return AVERROR_INVALIDDATA;
 74    }
 75
 76    p->reference = 0;
 77    if ((ret = avctx->get_buffer(avctx, p)) < 0) {
 78        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
 79        return ret;
 80    }
 81    p->pict_type = AV_PICTURE_TYPE_I;
 82    p->key_frame = 1;
 83
 84    init_get_bits(&gb, buf, buf_size * 8);
 85
 86    for (y = 0; y < avctx->height; y++) {
 87        uint8_t *luma = &a->picture.data[0][y * a->picture.linesize[0]];
 88        uint8_t *cb   = &a->picture.data[1][y * a->picture.linesize[1]];
 89        uint8_t *cr   = &a->picture.data[2][y * a->picture.linesize[2]];
 90        for (x = 0; x < avctx->width; x += 4) {
 91            luma[3] = (get_bits(&gb, 5)*33) >> 2;
 92            luma[2] = (get_bits(&gb, 5)*33) >> 2;
 93            luma[1] = (get_bits(&gb, 5)*33) >> 2;
 94            luma[0] = (get_bits(&gb, 5)*33) >> 2;
 95            luma += 4;
 96            *(cb++) = get_bits(&gb, 6) << 2;
 97            *(cr++) = get_bits(&gb, 6) << 2;
 98        }
 99    }
100
101    *picture   = a->picture;
102    *data_size = sizeof(AVPicture);
103
104    return buf_size;
105}
106
107static av_cold int decode_init(AVCodecContext *avctx)
108{
109    avctx->pix_fmt = AV_PIX_FMT_YUV411P;
110    return common_init(avctx);
111}
112
113static av_cold int decode_end(AVCodecContext *avctx)
114{
115    CLJRContext *a = avctx->priv_data;
116
117    if (a->picture.data[0])
118        avctx->release_buffer(avctx, &a->picture);
119    return 0;
120}
121
122AVCodec ff_cljr_decoder = {
123    .name           = "cljr",
124    .type           = AVMEDIA_TYPE_VIDEO,
125    .id             = AV_CODEC_ID_CLJR,
126    .priv_data_size = sizeof(CLJRContext),
127    .init           = decode_init,
128    .close          = decode_end,
129    .decode         = decode_frame,
130    .capabilities   = CODEC_CAP_DR1,
131    .long_name      = NULL_IF_CONFIG_SMALL("Cirrus Logic AccuPak"),
132};
133#endif
134
135#if CONFIG_CLJR_ENCODER
136static int encode_frame(AVCodecContext *avctx, AVPacket *pkt,
137                        const AVFrame *p, int *got_packet)
138{
139    CLJRContext *a = avctx->priv_data;
140    PutBitContext pb;
141    int x, y, ret;
142    uint32_t dither= avctx->frame_number;
143    static const uint32_t ordered_dither[2][2] =
144    {
145        { 0x10400000, 0x104F0000 },
146        { 0xCB2A0000, 0xCB250000 },
147    };
148
149    if ((ret = ff_alloc_packet2(avctx, pkt, 32*avctx->height*avctx->width/4)) < 0)
150        return ret;
151
152    avctx->coded_frame->pict_type = AV_PICTURE_TYPE_I;
153    avctx->coded_frame->key_frame = 1;
154
155    init_put_bits(&pb, pkt->data, pkt->size);
156
157    for (y = 0; y < avctx->height; y++) {
158        uint8_t *luma = &p->data[0][y * p->linesize[0]];
159        uint8_t *cb   = &p->data[1][y * p->linesize[1]];
160        uint8_t *cr   = &p->data[2][y * p->linesize[2]];
161        for (x = 0; x < avctx->width; x += 4) {
162            switch (a->dither_type) {
163            case 0: dither = 0x492A0000;                       break;
164            case 1: dither = dither * 1664525 + 1013904223;    break;
165            case 2: dither = ordered_dither[ y&1 ][ (x>>2)&1 ];break;
166            }
167            put_bits(&pb, 5, (249*(luma[3] +  (dither>>29)   )) >> 11);
168            put_bits(&pb, 5, (249*(luma[2] + ((dither>>26)&7))) >> 11);
169            put_bits(&pb, 5, (249*(luma[1] + ((dither>>23)&7))) >> 11);
170            put_bits(&pb, 5, (249*(luma[0] + ((dither>>20)&7))) >> 11);
171            luma += 4;
172            put_bits(&pb, 6, (253*(*(cb++) + ((dither>>18)&3))) >> 10);
173            put_bits(&pb, 6, (253*(*(cr++) + ((dither>>16)&3))) >> 10);
174        }
175    }
176
177    flush_put_bits(&pb);
178
179    pkt->size   = put_bits_count(&pb) / 8;
180    pkt->flags |= AV_PKT_FLAG_KEY;
181    *got_packet = 1;
182    return 0;
183}
184
185#define OFFSET(x) offsetof(CLJRContext, x)
186#define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
187static const AVOption options[] = {
188    { "dither_type",   "Dither type",   OFFSET(dither_type),        AV_OPT_TYPE_INT, { .i64=1 }, 0, 2, VE},
189    { NULL },
190};
191
192static const AVClass class = {
193    .class_name = "cljr encoder",
194    .item_name  = av_default_item_name,
195    .option     = options,
196    .version    = LIBAVUTIL_VERSION_INT,
197};
198
199AVCodec ff_cljr_encoder = {
200    .name           = "cljr",
201    .type           = AVMEDIA_TYPE_VIDEO,
202    .id             = AV_CODEC_ID_CLJR,
203    .priv_data_size = sizeof(CLJRContext),
204    .init           = common_init,
205    .encode2        = encode_frame,
206    .pix_fmts       = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV411P,
207                                                   AV_PIX_FMT_NONE },
208    .long_name      = NULL_IF_CONFIG_SMALL("Cirrus Logic AccuPak"),
209    .priv_class     = &class,
210};
211#endif