yading@10: /*
yading@10:  * Quicktime Animation (RLE) Video Encoder
yading@10:  * Copyright (C) 2007 Clemens Fruhwirth
yading@10:  * Copyright (C) 2007 Alexis Ballier
yading@10:  *
yading@10:  * This file is based on flashsvenc.c.
yading@10:  *
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: #include "libavutil/imgutils.h"
yading@10: #include "avcodec.h"
yading@10: #include "bytestream.h"
yading@10: #include "internal.h"
yading@10: 
yading@10: /** Maximum RLE code for bulk copy */
yading@10: #define MAX_RLE_BULK   127
yading@10: /** Maximum RLE code for repeat */
yading@10: #define MAX_RLE_REPEAT 128
yading@10: /** Maximum RLE code for skip */
yading@10: #define MAX_RLE_SKIP   254
yading@10: 
yading@10: typedef struct QtrleEncContext {
yading@10:     AVCodecContext *avctx;
yading@10:     AVFrame frame;
yading@10:     int pixel_size;
yading@10:     AVPicture previous_frame;
yading@10:     unsigned int max_buf_size;
yading@10:     int logical_width;
yading@10:     /**
yading@10:      * This array will contain at ith position the value of the best RLE code
yading@10:      * if the line started at pixel i
yading@10:      * There can be 3 values :
yading@10:      * skip (0)     : skip as much as possible pixels because they are equal to the
yading@10:      *                previous frame ones
yading@10:      * repeat (<-1) : repeat that pixel -rle_code times, still as much as
yading@10:      *                possible
yading@10:      * copy (>0)    : copy the raw next rle_code pixels */
yading@10:     signed char *rlecode_table;
yading@10:     /**
yading@10:      * This array will contain the length of the best rle encoding of the line
yading@10:      * starting at ith pixel */
yading@10:     int *length_table;
yading@10:     /**
yading@10:      * Will contain at ith position the number of consecutive pixels equal to the previous
yading@10:      * frame starting from pixel i */
yading@10:     uint8_t* skip_table;
yading@10: } QtrleEncContext;
yading@10: 
yading@10: static av_cold int qtrle_encode_init(AVCodecContext *avctx)
yading@10: {
yading@10:     QtrleEncContext *s = avctx->priv_data;
yading@10:     int ret;
yading@10: 
yading@10:     if (av_image_check_size(avctx->width, avctx->height, 0, avctx) < 0) {
yading@10:         return AVERROR(EINVAL);
yading@10:     }
yading@10:     s->avctx=avctx;
yading@10:     s->logical_width=avctx->width;
yading@10: 
yading@10:     switch (avctx->pix_fmt) {
yading@10:     case AV_PIX_FMT_GRAY8:
yading@10:         s->logical_width = avctx->width / 4;
yading@10:         s->pixel_size = 4;
yading@10:         break;
yading@10:     case AV_PIX_FMT_RGB555BE:
yading@10:         s->pixel_size = 2;
yading@10:         break;
yading@10:     case AV_PIX_FMT_RGB24:
yading@10:         s->pixel_size = 3;
yading@10:         break;
yading@10:     case AV_PIX_FMT_ARGB:
yading@10:         s->pixel_size = 4;
yading@10:         break;
yading@10:     default:
yading@10:         av_log(avctx, AV_LOG_ERROR, "Unsupported colorspace.\n");
yading@10:         break;
yading@10:     }
yading@10:     avctx->bits_per_coded_sample = avctx->pix_fmt == AV_PIX_FMT_GRAY8 ? 40 : s->pixel_size*8;
yading@10: 
yading@10:     s->rlecode_table = av_mallocz(s->logical_width);
yading@10:     s->skip_table    = av_mallocz(s->logical_width);
yading@10:     s->length_table  = av_mallocz((s->logical_width + 1)*sizeof(int));
yading@10:     if (!s->skip_table || !s->length_table || !s->rlecode_table) {
yading@10:         av_log(avctx, AV_LOG_ERROR, "Error allocating memory.\n");
yading@10:         return AVERROR(ENOMEM);
yading@10:     }
yading@10:     if ((ret = avpicture_alloc(&s->previous_frame, avctx->pix_fmt, avctx->width, avctx->height)) < 0) {
yading@10:         av_log(avctx, AV_LOG_ERROR, "Error allocating picture\n");
yading@10:         return ret;
yading@10:     }
yading@10: 
yading@10:     s->max_buf_size = s->logical_width*s->avctx->height*s->pixel_size*2 /* image base material */
yading@10:                       + 15                                            /* header + footer */
yading@10:                       + s->avctx->height*2                            /* skip code+rle end */
yading@10:                       + s->logical_width/MAX_RLE_BULK + 1             /* rle codes */;
yading@10:     avctx->coded_frame = &s->frame;
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * Compute the best RLE sequence for a line
yading@10:  */
yading@10: static void qtrle_encode_line(QtrleEncContext *s, const AVFrame *p, int line, uint8_t **buf)
yading@10: {
yading@10:     int width=s->logical_width;
yading@10:     int i;
yading@10:     signed char rlecode;
yading@10: 
yading@10:     /* This will be the number of pixels equal to the preivous frame one's
yading@10:      * starting from the ith pixel */
yading@10:     unsigned int skipcount;
yading@10:     /* This will be the number of consecutive equal pixels in the current
yading@10:      * frame, starting from the ith one also */
yading@10:     unsigned int av_uninit(repeatcount);
yading@10: 
yading@10:     /* The cost of the three different possibilities */
yading@10:     int total_skip_cost;
yading@10:     int total_repeat_cost;
yading@10: 
yading@10:     int base_bulk_cost;
yading@10:     int lowest_bulk_cost;
yading@10:     int lowest_bulk_cost_index;
yading@10:     int sec_lowest_bulk_cost;
yading@10:     int sec_lowest_bulk_cost_index;
yading@10: 
yading@10:     uint8_t *this_line = p->               data[0] + line*p->               linesize[0] +
yading@10:         (width - 1)*s->pixel_size;
yading@10:     uint8_t *prev_line = s->previous_frame.data[0] + line*s->previous_frame.linesize[0] +
yading@10:         (width - 1)*s->pixel_size;
yading@10: 
yading@10:     s->length_table[width] = 0;
yading@10:     skipcount = 0;
yading@10: 
yading@10:     /* Initial values */
yading@10:     lowest_bulk_cost = INT_MAX / 2;
yading@10:     lowest_bulk_cost_index = width;
yading@10:     sec_lowest_bulk_cost = INT_MAX / 2;
yading@10:     sec_lowest_bulk_cost_index = width;
yading@10: 
yading@10:     base_bulk_cost = 1 + s->pixel_size;
yading@10: 
yading@10:     for (i = width - 1; i >= 0; i--) {
yading@10: 
yading@10:         int prev_bulk_cost;
yading@10: 
yading@10:         /* If our lowest bulk cost index is too far away, replace it
yading@10:          * with the next lowest bulk cost */
yading@10:         if (FFMIN(width, i + MAX_RLE_BULK) < lowest_bulk_cost_index) {
yading@10:             lowest_bulk_cost = sec_lowest_bulk_cost;
yading@10:             lowest_bulk_cost_index = sec_lowest_bulk_cost_index;
yading@10: 
yading@10:             sec_lowest_bulk_cost = INT_MAX / 2;
yading@10:             sec_lowest_bulk_cost_index = width;
yading@10:         }
yading@10: 
yading@10:         /* Deal with the first pixel's bulk cost */
yading@10:         if (!i) {
yading@10:             base_bulk_cost++;
yading@10:             lowest_bulk_cost++;
yading@10:             sec_lowest_bulk_cost++;
yading@10:         }
yading@10: 
yading@10:         /* Look at the bulk cost of the previous loop and see if it is
yading@10:          * a new lower bulk cost */
yading@10:         prev_bulk_cost = s->length_table[i + 1] + base_bulk_cost;
yading@10:         if (prev_bulk_cost <= sec_lowest_bulk_cost) {
yading@10:             /* If it's lower than the 2nd lowest, then it may be lower
yading@10:              * than the lowest */
yading@10:             if (prev_bulk_cost <= lowest_bulk_cost) {
yading@10: 
yading@10:                 /* If we have found a new lowest bulk cost,
yading@10:                  * then the 2nd lowest bulk cost is now farther than the
yading@10:                  * lowest bulk cost, and will never be used */
yading@10:                 sec_lowest_bulk_cost = INT_MAX / 2;
yading@10: 
yading@10:                 lowest_bulk_cost = prev_bulk_cost;
yading@10:                 lowest_bulk_cost_index = i + 1;
yading@10:             } else {
yading@10:                 /* Then it must be the 2nd lowest bulk cost */
yading@10:                 sec_lowest_bulk_cost = prev_bulk_cost;
yading@10:                 sec_lowest_bulk_cost_index = i + 1;
yading@10:             }
yading@10:         }
yading@10: 
yading@10:         if (!s->frame.key_frame && !memcmp(this_line, prev_line, s->pixel_size))
yading@10:             skipcount = FFMIN(skipcount + 1, MAX_RLE_SKIP);
yading@10:         else
yading@10:             skipcount = 0;
yading@10: 
yading@10:         total_skip_cost  = s->length_table[i + skipcount] + 2;
yading@10:         s->skip_table[i] = skipcount;
yading@10: 
yading@10: 
yading@10:         if (i < width - 1 && !memcmp(this_line, this_line + s->pixel_size, s->pixel_size))
yading@10:             repeatcount = FFMIN(repeatcount + 1, MAX_RLE_REPEAT);
yading@10:         else
yading@10:             repeatcount = 1;
yading@10: 
yading@10:         total_repeat_cost = s->length_table[i + repeatcount] + 1 + s->pixel_size;
yading@10: 
yading@10:         /* skip code is free for the first pixel, it costs one byte for repeat and bulk copy
yading@10:          * so let's make it aware */
yading@10:         if (i == 0) {
yading@10:             total_skip_cost--;
yading@10:             total_repeat_cost++;
yading@10:         }
yading@10: 
yading@10:         if (repeatcount > 1 && (skipcount == 0 || total_repeat_cost < total_skip_cost)) {
yading@10:             /* repeat is the best */
yading@10:             s->length_table[i]  = total_repeat_cost;
yading@10:             s->rlecode_table[i] = -repeatcount;
yading@10:         }
yading@10:         else if (skipcount > 0) {
yading@10:             /* skip is the best choice here */
yading@10:             s->length_table[i]  = total_skip_cost;
yading@10:             s->rlecode_table[i] = 0;
yading@10:         }
yading@10:         else {
yading@10:             /* We cannot do neither skip nor repeat
yading@10:              * thus we use the best bulk copy  */
yading@10: 
yading@10:             s->length_table[i]  = lowest_bulk_cost;
yading@10:             s->rlecode_table[i] = lowest_bulk_cost_index - i;
yading@10: 
yading@10:         }
yading@10: 
yading@10:         /* These bulk costs increase every iteration */
yading@10:         lowest_bulk_cost += s->pixel_size;
yading@10:         sec_lowest_bulk_cost += s->pixel_size;
yading@10: 
yading@10:         this_line -= s->pixel_size;
yading@10:         prev_line -= s->pixel_size;
yading@10:     }
yading@10: 
yading@10:     /* Good ! Now we have the best sequence for this line, let's output it */
yading@10: 
yading@10:     /* We do a special case for the first pixel so that we avoid testing it in
yading@10:      * the whole loop */
yading@10: 
yading@10:     i=0;
yading@10:     this_line = p->               data[0] + line*p->linesize[0];
yading@10: 
yading@10:     if (s->rlecode_table[0] == 0) {
yading@10:         bytestream_put_byte(buf, s->skip_table[0] + 1);
yading@10:         i += s->skip_table[0];
yading@10:     }
yading@10:     else bytestream_put_byte(buf, 1);
yading@10: 
yading@10: 
yading@10:     while (i < width) {
yading@10:         rlecode = s->rlecode_table[i];
yading@10:         bytestream_put_byte(buf, rlecode);
yading@10:         if (rlecode == 0) {
yading@10:             /* Write a skip sequence */
yading@10:             bytestream_put_byte(buf, s->skip_table[i] + 1);
yading@10:             i += s->skip_table[i];
yading@10:         }
yading@10:         else if (rlecode > 0) {
yading@10:             /* bulk copy */
yading@10:             if (s->avctx->pix_fmt == AV_PIX_FMT_GRAY8) {
yading@10:                 int j;
yading@10:                 // QT grayscale colorspace has 0=white and 255=black, we will
yading@10:                 // ignore the palette that is included in the AVFrame because
yading@10:                 // AV_PIX_FMT_GRAY8 has defined color mapping
yading@10:                 for (j = 0; j < rlecode*s->pixel_size; ++j)
yading@10:                     bytestream_put_byte(buf, *(this_line + i*s->pixel_size + j) ^ 0xff);
yading@10:             } else {
yading@10:                 bytestream_put_buffer(buf, this_line + i*s->pixel_size, rlecode*s->pixel_size);
yading@10:             }
yading@10:             i += rlecode;
yading@10:         }
yading@10:         else {
yading@10:             /* repeat the bits */
yading@10:             if (s->avctx->pix_fmt == AV_PIX_FMT_GRAY8) {
yading@10:                 int j;
yading@10:                 // QT grayscale colorspace has 0=white and 255=black, ...
yading@10:                 for (j = 0; j < s->pixel_size; ++j)
yading@10:                     bytestream_put_byte(buf, *(this_line + i*s->pixel_size + j) ^ 0xff);
yading@10:             } else {
yading@10:                 bytestream_put_buffer(buf, this_line + i*s->pixel_size, s->pixel_size);
yading@10:             }
yading@10:             i -= rlecode;
yading@10:         }
yading@10:     }
yading@10:     bytestream_put_byte(buf, -1); // end RLE line
yading@10: }
yading@10: 
yading@10: /** Encode frame including header */
yading@10: static int encode_frame(QtrleEncContext *s, const AVFrame *p, uint8_t *buf)
yading@10: {
yading@10:     int i;
yading@10:     int start_line = 0;
yading@10:     int end_line = s->avctx->height;
yading@10:     uint8_t *orig_buf = buf;
yading@10: 
yading@10:     if (!s->frame.key_frame) {
yading@10:         unsigned line_size = s->logical_width * s->pixel_size;
yading@10:         for (start_line = 0; start_line < s->avctx->height; start_line++)
yading@10:             if (memcmp(p->data[0] + start_line*p->linesize[0],
yading@10:                        s->previous_frame.data[0] + start_line*s->previous_frame.linesize[0],
yading@10:                        line_size))
yading@10:                 break;
yading@10: 
yading@10:         for (end_line=s->avctx->height; end_line > start_line; end_line--)
yading@10:             if (memcmp(p->data[0] + (end_line - 1)*p->linesize[0],
yading@10:                        s->previous_frame.data[0] + (end_line - 1)*s->previous_frame.linesize[0],
yading@10:                        line_size))
yading@10:                 break;
yading@10:     }
yading@10: 
yading@10:     bytestream_put_be32(&buf, 0);                         // CHUNK SIZE, patched later
yading@10: 
yading@10:     if ((start_line == 0 && end_line == s->avctx->height) || start_line == s->avctx->height)
yading@10:         bytestream_put_be16(&buf, 0);                     // header
yading@10:     else {
yading@10:         bytestream_put_be16(&buf, 8);                     // header
yading@10:         bytestream_put_be16(&buf, start_line);            // starting line
yading@10:         bytestream_put_be16(&buf, 0);                     // unknown
yading@10:         bytestream_put_be16(&buf, end_line - start_line); // lines to update
yading@10:         bytestream_put_be16(&buf, 0);                     // unknown
yading@10:     }
yading@10:     for (i = start_line; i < end_line; i++)
yading@10:         qtrle_encode_line(s, p, i, &buf);
yading@10: 
yading@10:     bytestream_put_byte(&buf, 0);                         // zero skip code = frame finished
yading@10:     AV_WB32(orig_buf, buf - orig_buf);                    // patch the chunk size
yading@10:     return buf - orig_buf;
yading@10: }
yading@10: 
yading@10: static int qtrle_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
yading@10:                               const AVFrame *pict, int *got_packet)
yading@10: {
yading@10:     QtrleEncContext * const s = avctx->priv_data;
yading@10:     AVFrame * const p = &s->frame;
yading@10:     int ret;
yading@10: 
yading@10:     *p = *pict;
yading@10: 
yading@10:     if ((ret = ff_alloc_packet2(avctx, pkt, s->max_buf_size)) < 0)
yading@10:         return ret;
yading@10: 
yading@10:     if (avctx->gop_size == 0 || (s->avctx->frame_number % avctx->gop_size) == 0) {
yading@10:         /* I-Frame */
yading@10:         p->pict_type = AV_PICTURE_TYPE_I;
yading@10:         p->key_frame = 1;
yading@10:     } else {
yading@10:         /* P-Frame */
yading@10:         p->pict_type = AV_PICTURE_TYPE_P;
yading@10:         p->key_frame = 0;
yading@10:     }
yading@10: 
yading@10:     pkt->size = encode_frame(s, pict, pkt->data);
yading@10: 
yading@10:     /* save the current frame */
yading@10:     av_picture_copy(&s->previous_frame, (AVPicture *)p, avctx->pix_fmt, avctx->width, avctx->height);
yading@10: 
yading@10:     if (p->key_frame)
yading@10:         pkt->flags |= AV_PKT_FLAG_KEY;
yading@10:     *got_packet = 1;
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static av_cold int qtrle_encode_end(AVCodecContext *avctx)
yading@10: {
yading@10:     QtrleEncContext *s = avctx->priv_data;
yading@10: 
yading@10:     avpicture_free(&s->previous_frame);
yading@10:     av_free(s->rlecode_table);
yading@10:     av_free(s->length_table);
yading@10:     av_free(s->skip_table);
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: AVCodec ff_qtrle_encoder = {
yading@10:     .name           = "qtrle",
yading@10:     .type           = AVMEDIA_TYPE_VIDEO,
yading@10:     .id             = AV_CODEC_ID_QTRLE,
yading@10:     .priv_data_size = sizeof(QtrleEncContext),
yading@10:     .init           = qtrle_encode_init,
yading@10:     .encode2        = qtrle_encode_frame,
yading@10:     .close          = qtrle_encode_end,
yading@10:     .pix_fmts       = (const enum AVPixelFormat[]){
yading@10:         AV_PIX_FMT_RGB24, AV_PIX_FMT_RGB555BE, AV_PIX_FMT_ARGB, AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE
yading@10:     },
yading@10:     .long_name      = NULL_IF_CONFIG_SMALL("QuickTime Animation (RLE) video"),
yading@10: };