diff options
Diffstat (limited to 'ffmpeg1/libavcodec/zerocodec.c')
| -rw-r--r-- | ffmpeg1/libavcodec/zerocodec.c | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/ffmpeg1/libavcodec/zerocodec.c b/ffmpeg1/libavcodec/zerocodec.c new file mode 100644 index 0000000..4a23b67 --- /dev/null +++ b/ffmpeg1/libavcodec/zerocodec.c @@ -0,0 +1,146 @@ +/* + * ZeroCodec Decoder + * + * Copyright (c) 2012, Derek Buitenhuis + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#include <zlib.h> + +#include "avcodec.h" +#include "internal.h" +#include "libavutil/common.h" + +typedef struct { + AVFrame previous_frame; + z_stream zstream; +} ZeroCodecContext; + +static int zerocodec_decode_frame(AVCodecContext *avctx, void *data, + int *got_frame, AVPacket *avpkt) +{ + ZeroCodecContext *zc = avctx->priv_data; + AVFrame *pic = data; + AVFrame *prev_pic = &zc->previous_frame; + z_stream *zstream = &zc->zstream; + uint8_t *prev = prev_pic->data[0]; + uint8_t *dst; + int i, j, zret, ret; + + if (avpkt->flags & AV_PKT_FLAG_KEY) { + pic->key_frame = 1; + pic->pict_type = AV_PICTURE_TYPE_I; + } else { + if (!prev) { + av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n"); + return AVERROR_INVALIDDATA; + } + + prev += (avctx->height - 1) * prev_pic->linesize[0]; + + pic->key_frame = 0; + pic->pict_type = AV_PICTURE_TYPE_P; + } + + zret = inflateReset(zstream); + if (zret != Z_OK) { + av_log(avctx, AV_LOG_ERROR, "Could not reset inflate: %d.\n", zret); + return AVERROR_INVALIDDATA; + } + + if ((ret = ff_get_buffer(avctx, pic, AV_GET_BUFFER_FLAG_REF)) < 0) + return ret; + + zstream->next_in = avpkt->data; + zstream->avail_in = avpkt->size; + + dst = pic->data[0] + (avctx->height - 1) * pic->linesize[0]; + + /** + * ZeroCodec has very simple interframe compression. If a value + * is the same as the previous frame, set it to 0. + */ + + for (i = 0; i < avctx->height; i++) { + zstream->next_out = dst; + zstream->avail_out = avctx->width << 1; + + zret = inflate(zstream, Z_SYNC_FLUSH); + if (zret != Z_OK && zret != Z_STREAM_END) { + av_log(avctx, AV_LOG_ERROR, + "Inflate failed with return code: %d.\n", zret); + return AVERROR_INVALIDDATA; + } + + if (!(avpkt->flags & AV_PKT_FLAG_KEY)) + for (j = 0; j < avctx->width << 1; j++) + dst[j] += prev[j] & -!dst[j]; + + prev -= prev_pic->linesize[0]; + dst -= pic->linesize[0]; + } + + av_frame_unref(&zc->previous_frame); + if ((ret = av_frame_ref(&zc->previous_frame, pic)) < 0) + return ret; + + *got_frame = 1; + + return avpkt->size; +} + +static av_cold int zerocodec_decode_close(AVCodecContext *avctx) +{ + ZeroCodecContext *zc = avctx->priv_data; + + av_frame_unref(&zc->previous_frame); + + inflateEnd(&zc->zstream); + + return 0; +} + +static av_cold int zerocodec_decode_init(AVCodecContext *avctx) +{ + ZeroCodecContext *zc = avctx->priv_data; + z_stream *zstream = &zc->zstream; + int zret; + + avctx->pix_fmt = AV_PIX_FMT_UYVY422; + avctx->bits_per_raw_sample = 8; + + zstream->zalloc = Z_NULL; + zstream->zfree = Z_NULL; + zstream->opaque = Z_NULL; + + zret = inflateInit(zstream); + if (zret != Z_OK) { + av_log(avctx, AV_LOG_ERROR, "Could not initialize inflate: %d.\n", zret); + return AVERROR(ENOMEM); + } + + return 0; +} + +AVCodec ff_zerocodec_decoder = { + .type = AVMEDIA_TYPE_VIDEO, + .name = "zerocodec", + .id = AV_CODEC_ID_ZEROCODEC, + .priv_data_size = sizeof(ZeroCodecContext), + .init = zerocodec_decode_init, + .decode = zerocodec_decode_frame, + .close = zerocodec_decode_close, + .capabilities = CODEC_CAP_DR1, + .long_name = NULL_IF_CONFIG_SMALL("ZeroCodec Lossless Video"), +}; |
