| /* |
| * PDV video format |
| * |
| * Copyright (c) 2023 Paul B Mahol |
| * |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * FFmpeg is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| #include "avcodec.h" |
| #include "codec_internal.h" |
| #include "decode.h" |
| #include "zlib_wrapper.h" |
| |
| #include <zlib.h> |
| |
| typedef struct PDVContext { |
| AVFrame *previous_frame; |
| FFZStream zstream; |
| } PDVContext; |
| |
| static av_cold int decode_init(AVCodecContext *avctx) |
| { |
| PDVContext *s = avctx->priv_data; |
| |
| avctx->pix_fmt = AV_PIX_FMT_MONOBLACK; |
| |
| s->previous_frame = av_frame_alloc(); |
| if (!s->previous_frame) |
| return AVERROR(ENOMEM); |
| |
| return ff_inflate_init(&s->zstream, avctx); |
| } |
| |
| static av_cold int decode_end(AVCodecContext *avctx) |
| { |
| PDVContext *s = avctx->priv_data; |
| |
| av_frame_free(&s->previous_frame); |
| ff_inflate_end(&s->zstream); |
| |
| return 0; |
| } |
| |
| static int decode_frame(AVCodecContext *avctx, AVFrame *frame, |
| int *got_frame, AVPacket *avpkt) |
| { |
| PDVContext *s = avctx->priv_data; |
| AVFrame *prev_frame = s->previous_frame; |
| z_stream *const zstream = &s->zstream.zstream; |
| uint8_t *dst, *prev = prev_frame->data[0]; |
| int ret, zret; |
| |
| if (avctx->skip_frame >= AVDISCARD_ALL || |
| (avctx->skip_frame >= AVDISCARD_NONINTRA && |
| !(avpkt->flags & AV_PKT_FLAG_KEY))) |
| return avpkt->size; |
| |
| 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, frame, AV_GET_BUFFER_FLAG_REF)) < 0) |
| return ret; |
| |
| zstream->next_in = avpkt->data; |
| zstream->avail_in = avpkt->size; |
| |
| dst = frame->data[0]; |
| for (int i = 0; i < avctx->height; i++) { |
| zstream->next_out = dst; |
| zstream->avail_out = (avctx->width + 7) >> 3; |
| |
| 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 (prev && !(avpkt->flags & AV_PKT_FLAG_KEY)) { |
| for (int j = 0; j < (avctx->width + 7) >> 3; j++) |
| dst[j] ^= prev[j]; |
| prev += prev_frame->linesize[0]; |
| } |
| |
| dst += frame->linesize[0]; |
| } |
| |
| if ((ret = av_frame_replace(s->previous_frame, frame)) < 0) |
| return ret; |
| |
| if (avpkt->flags & AV_PKT_FLAG_KEY) { |
| frame->flags |= AV_FRAME_FLAG_KEY; |
| frame->pict_type = AV_PICTURE_TYPE_I; |
| } else { |
| frame->pict_type = AV_PICTURE_TYPE_P; |
| } |
| |
| *got_frame = 1; |
| |
| return avpkt->size; |
| } |
| |
| static void decode_flush(AVCodecContext *avctx) |
| { |
| PDVContext *s = avctx->priv_data; |
| |
| av_frame_unref(s->previous_frame); |
| } |
| |
| const FFCodec ff_pdv_decoder = { |
| .p.name = "pdv", |
| CODEC_LONG_NAME("PDV (PlayDate Video)"), |
| .priv_data_size = sizeof(PDVContext), |
| .p.type = AVMEDIA_TYPE_VIDEO, |
| .p.id = AV_CODEC_ID_PDV, |
| .p.capabilities = AV_CODEC_CAP_DR1, |
| .caps_internal = FF_CODEC_CAP_SKIP_FRAME_FILL_PARAM | |
| FF_CODEC_CAP_INIT_CLEANUP, |
| .init = decode_init, |
| .close = decode_end, |
| .flush = decode_flush, |
| FF_CODEC_DECODE_CB(decode_frame), |
| }; |