Function encode_scanline_rle

libavcodec/exrenc.c:221–277

}

static int encode_scanline_rle(EXRContext *s, const AVFrame *frame)
{
    const int64_t element_size = s->pixel_type == EXR_HALF ? 2LL : 4LL;

    for (int y = 0; y < frame->height; y++) {
        EXRScanlineData *scanline = &s->scanline[y];
        int64_t tmp_size = element_size * s->planes * frame->width;
        int64_t max_compressed_size = tmp_size * 3 / 2;

        av_fast_padded_malloc(&scanline->uncompressed_data, &scanline->uncompressed_size, tmp_size);
        if (!scanline->uncompressed_data)
            return AVERROR(ENOMEM);

        av_fast_padded_malloc(&scanline->tmp, &scanline->tmp_size, tmp_size);
        if (!scanline->tmp)
            return AVERROR(ENOMEM);

        av_fast_padded_malloc(&scanline->compressed_data, &scanline->compressed_size, max_compressed_size);
        if (!scanline->compressed_data)
            return AVERROR(ENOMEM);

        switch (s->pixel_type) {
        case EXR_FLOAT:
            for (int p = 0; p < s->planes; p++) {
                int ch = s->ch_order[p];

                memcpy(scanline->uncompressed_data + frame->width * 4 * p,
                       frame->data[ch] + y * frame->linesize[ch], frame->width * 4);
            }
            break;
        case EXR_HALF:
            for (int p = 0; p < s->planes; p++) {
                int ch = s->ch_order[p];
                uint16_t *dst = (uint16_t *)(scanline->uncompressed_data + frame->width * 2 * p);
                const uint32_t *src = (const uint32_t *)(frame->data[ch] + y * frame->linesize[ch]);

                for (int x = 0; x < frame->width; x++)
                    dst[x] = float2half(src[x], &s->f2h_tables);
            }
            break;
        }

        reorder_pixels(scanline->tmp, scanline->uncompressed_data, tmp_size);
        predictor(scanline->tmp, tmp_size);
        scanline->actual_size = rle_compress(scanline->compressed_data,
                                             max_compressed_size,
                                             scanline->tmp, tmp_size);

        if (scanline->actual_size <= 0 || scanline->actual_size >= tmp_size) {
            FFSWAP(uint8_t *, scanline->uncompressed_data, scanline->compressed_data);
            FFSWAP(int, scanline->uncompressed_size, scanline->compressed_size);
            scanline->actual_size = tmp_size;
        }
    }

    return 0;
}