| 1 | /* |
| 2 | * Cirrus Logic AccuPak (CLJR) encoder |
| 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 encoder. |
| 25 | */ |
| 26 | |
| 27 | #include "libavutil/common.h" |
| 28 | #include "libavutil/opt.h" |
| 29 | |
| 30 | #include "avcodec.h" |
| 31 | #include "internal.h" |
| 32 | #include "put_bits.h" |
| 33 | |
| 34 | typedef struct CLJRContext { |
| 35 | AVClass *avclass; |
| 36 | int dither_type; |
| 37 | } CLJRContext; |
| 38 | |
| 39 | static int encode_frame(AVCodecContext *avctx, AVPacket *pkt, |
| 40 | const AVFrame *p, int *got_packet) |
| 41 | { |
| 42 | CLJRContext *a = avctx->priv_data; |
| 43 | PutBitContext pb; |
| 44 | int x, y, ret; |
| 45 | uint32_t dither= avctx->frame_number; |
| 46 | static const uint32_t ordered_dither[2][2] = |
| 47 | { |
| 48 | { 0x10400000, 0x104F0000 }, |
| 49 | { 0xCB2A0000, 0xCB250000 }, |
| 50 | }; |
| 51 | |
| 52 | if (avctx->width%4 && avctx->strict_std_compliance > FF_COMPLIANCE_UNOFFICIAL) { |
| 53 | av_log(avctx, AV_LOG_ERROR, |
| 54 | "Widths which are not a multiple of 4 might fail with some decoders, " |
| 55 | "use vstrict=-1 / -strict -1 to use %d anyway.\n", avctx->width); |
| 56 | return AVERROR_EXPERIMENTAL; |
| 57 | } |
| 58 | |
| 59 | if ((ret = ff_alloc_packet2(avctx, pkt, 32*avctx->height*avctx->width/4)) < 0) |
| 60 | return ret; |
| 61 | |
| 62 | init_put_bits(&pb, pkt->data, pkt->size); |
| 63 | |
| 64 | for (y = 0; y < avctx->height; y++) { |
| 65 | uint8_t *luma = &p->data[0][y * p->linesize[0]]; |
| 66 | uint8_t *cb = &p->data[1][y * p->linesize[1]]; |
| 67 | uint8_t *cr = &p->data[2][y * p->linesize[2]]; |
| 68 | uint8_t luma_tmp[4]; |
| 69 | for (x = 0; x < avctx->width; x += 4) { |
| 70 | switch (a->dither_type) { |
| 71 | case 0: dither = 0x492A0000; break; |
| 72 | case 1: dither = dither * 1664525 + 1013904223; break; |
| 73 | case 2: dither = ordered_dither[ y&1 ][ (x>>2)&1 ];break; |
| 74 | } |
| 75 | if (x+3 >= avctx->width) { |
| 76 | memset(luma_tmp, 0, sizeof(luma_tmp)); |
| 77 | memcpy(luma_tmp, luma, avctx->width - x); |
| 78 | luma = luma_tmp; |
| 79 | } |
| 80 | put_bits(&pb, 5, (249*(luma[3] + (dither>>29) )) >> 11); |
| 81 | put_bits(&pb, 5, (249*(luma[2] + ((dither>>26)&7))) >> 11); |
| 82 | put_bits(&pb, 5, (249*(luma[1] + ((dither>>23)&7))) >> 11); |
| 83 | put_bits(&pb, 5, (249*(luma[0] + ((dither>>20)&7))) >> 11); |
| 84 | luma += 4; |
| 85 | put_bits(&pb, 6, (253*(*(cb++) + ((dither>>18)&3))) >> 10); |
| 86 | put_bits(&pb, 6, (253*(*(cr++) + ((dither>>16)&3))) >> 10); |
| 87 | } |
| 88 | } |
| 89 | |
| 90 | flush_put_bits(&pb); |
| 91 | |
| 92 | pkt->size = put_bits_count(&pb) / 8; |
| 93 | pkt->flags |= AV_PKT_FLAG_KEY; |
| 94 | *got_packet = 1; |
| 95 | return 0; |
| 96 | } |
| 97 | |
| 98 | #define OFFSET(x) offsetof(CLJRContext, x) |
| 99 | #define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM |
| 100 | static const AVOption options[] = { |
| 101 | { "dither_type", "Dither type", OFFSET(dither_type), AV_OPT_TYPE_INT, { .i64=1 }, 0, 2, VE}, |
| 102 | { NULL }, |
| 103 | }; |
| 104 | |
| 105 | static const AVClass cljr_class = { |
| 106 | .class_name = "cljr encoder", |
| 107 | .item_name = av_default_item_name, |
| 108 | .option = options, |
| 109 | .version = LIBAVUTIL_VERSION_INT, |
| 110 | }; |
| 111 | |
| 112 | AVCodec ff_cljr_encoder = { |
| 113 | .name = "cljr", |
| 114 | .long_name = NULL_IF_CONFIG_SMALL("Cirrus Logic AccuPak"), |
| 115 | .type = AVMEDIA_TYPE_VIDEO, |
| 116 | .id = AV_CODEC_ID_CLJR, |
| 117 | .priv_data_size = sizeof(CLJRContext), |
| 118 | .encode2 = encode_frame, |
| 119 | .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV411P, |
| 120 | AV_PIX_FMT_NONE }, |
| 121 | .priv_class = &cljr_class, |
| 122 | }; |