| 1 | /* |
| 2 | * ZeroCodec Decoder |
| 3 | * |
| 4 | * Copyright (c) 2012, Derek Buitenhuis |
| 5 | * |
| 6 | * Permission to use, copy, modify, and/or distribute this software for any |
| 7 | * purpose with or without fee is hereby granted, provided that the above |
| 8 | * copyright notice and this permission notice appear in all copies. |
| 9 | * |
| 10 | * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES |
| 11 | * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
| 12 | * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR |
| 13 | * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| 14 | * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN |
| 15 | * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF |
| 16 | * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
| 17 | */ |
| 18 | |
| 19 | #include <zlib.h> |
| 20 | |
| 21 | #include "avcodec.h" |
| 22 | #include "internal.h" |
| 23 | #include "libavutil/common.h" |
| 24 | |
| 25 | typedef struct { |
| 26 | AVFrame *previous_frame; |
| 27 | z_stream zstream; |
| 28 | } ZeroCodecContext; |
| 29 | |
| 30 | static int zerocodec_decode_frame(AVCodecContext *avctx, void *data, |
| 31 | int *got_frame, AVPacket *avpkt) |
| 32 | { |
| 33 | ZeroCodecContext *zc = avctx->priv_data; |
| 34 | AVFrame *pic = data; |
| 35 | AVFrame *prev_pic = zc->previous_frame; |
| 36 | z_stream *zstream = &zc->zstream; |
| 37 | uint8_t *prev = prev_pic->data[0]; |
| 38 | uint8_t *dst; |
| 39 | int i, j, zret, ret; |
| 40 | |
| 41 | if (avpkt->flags & AV_PKT_FLAG_KEY) { |
| 42 | pic->key_frame = 1; |
| 43 | pic->pict_type = AV_PICTURE_TYPE_I; |
| 44 | } else { |
| 45 | if (!prev) { |
| 46 | av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n"); |
| 47 | return AVERROR_INVALIDDATA; |
| 48 | } |
| 49 | |
| 50 | prev += (avctx->height - 1) * prev_pic->linesize[0]; |
| 51 | |
| 52 | pic->key_frame = 0; |
| 53 | pic->pict_type = AV_PICTURE_TYPE_P; |
| 54 | } |
| 55 | |
| 56 | zret = inflateReset(zstream); |
| 57 | if (zret != Z_OK) { |
| 58 | av_log(avctx, AV_LOG_ERROR, "Could not reset inflate: %d.\n", zret); |
| 59 | return AVERROR_INVALIDDATA; |
| 60 | } |
| 61 | |
| 62 | if ((ret = ff_get_buffer(avctx, pic, AV_GET_BUFFER_FLAG_REF)) < 0) |
| 63 | return ret; |
| 64 | |
| 65 | zstream->next_in = avpkt->data; |
| 66 | zstream->avail_in = avpkt->size; |
| 67 | |
| 68 | dst = pic->data[0] + (avctx->height - 1) * pic->linesize[0]; |
| 69 | |
| 70 | /** |
| 71 | * ZeroCodec has very simple interframe compression. If a value |
| 72 | * is the same as the previous frame, set it to 0. |
| 73 | */ |
| 74 | |
| 75 | for (i = 0; i < avctx->height; i++) { |
| 76 | zstream->next_out = dst; |
| 77 | zstream->avail_out = avctx->width << 1; |
| 78 | |
| 79 | zret = inflate(zstream, Z_SYNC_FLUSH); |
| 80 | if (zret != Z_OK && zret != Z_STREAM_END) { |
| 81 | av_log(avctx, AV_LOG_ERROR, |
| 82 | "Inflate failed with return code: %d.\n", zret); |
| 83 | return AVERROR_INVALIDDATA; |
| 84 | } |
| 85 | |
| 86 | if (!(avpkt->flags & AV_PKT_FLAG_KEY)) |
| 87 | for (j = 0; j < avctx->width << 1; j++) |
| 88 | dst[j] += prev[j] & -!dst[j]; |
| 89 | |
| 90 | prev -= prev_pic->linesize[0]; |
| 91 | dst -= pic->linesize[0]; |
| 92 | } |
| 93 | |
| 94 | av_frame_unref(zc->previous_frame); |
| 95 | if ((ret = av_frame_ref(zc->previous_frame, pic)) < 0) |
| 96 | return ret; |
| 97 | |
| 98 | *got_frame = 1; |
| 99 | |
| 100 | return avpkt->size; |
| 101 | } |
| 102 | |
| 103 | static av_cold int zerocodec_decode_close(AVCodecContext *avctx) |
| 104 | { |
| 105 | ZeroCodecContext *zc = avctx->priv_data; |
| 106 | |
| 107 | av_frame_free(&zc->previous_frame); |
| 108 | |
| 109 | inflateEnd(&zc->zstream); |
| 110 | |
| 111 | return 0; |
| 112 | } |
| 113 | |
| 114 | static av_cold int zerocodec_decode_init(AVCodecContext *avctx) |
| 115 | { |
| 116 | ZeroCodecContext *zc = avctx->priv_data; |
| 117 | z_stream *zstream = &zc->zstream; |
| 118 | int zret; |
| 119 | |
| 120 | avctx->pix_fmt = AV_PIX_FMT_UYVY422; |
| 121 | avctx->bits_per_raw_sample = 8; |
| 122 | |
| 123 | zstream->zalloc = Z_NULL; |
| 124 | zstream->zfree = Z_NULL; |
| 125 | zstream->opaque = Z_NULL; |
| 126 | |
| 127 | zret = inflateInit(zstream); |
| 128 | if (zret != Z_OK) { |
| 129 | av_log(avctx, AV_LOG_ERROR, "Could not initialize inflate: %d.\n", zret); |
| 130 | return AVERROR(ENOMEM); |
| 131 | } |
| 132 | |
| 133 | zc->previous_frame = av_frame_alloc(); |
| 134 | if (!zc->previous_frame) { |
| 135 | zerocodec_decode_close(avctx); |
| 136 | return AVERROR(ENOMEM); |
| 137 | } |
| 138 | |
| 139 | return 0; |
| 140 | } |
| 141 | |
| 142 | AVCodec ff_zerocodec_decoder = { |
| 143 | .type = AVMEDIA_TYPE_VIDEO, |
| 144 | .name = "zerocodec", |
| 145 | .long_name = NULL_IF_CONFIG_SMALL("ZeroCodec Lossless Video"), |
| 146 | .id = AV_CODEC_ID_ZEROCODEC, |
| 147 | .priv_data_size = sizeof(ZeroCodecContext), |
| 148 | .init = zerocodec_decode_init, |
| 149 | .decode = zerocodec_decode_frame, |
| 150 | .close = zerocodec_decode_close, |
| 151 | .capabilities = CODEC_CAP_DR1, |
| 152 | }; |